DUPONT VESPEL TP-8 SERIES DESIGN HANDBOOK SUITABLE FOR MECHANICAL COMPONENTS REQUIRING THERMAL AND CHEMICAL RESISTANCE, LOW WEAR AND FRICTION, AND ELECTRICAL PERFORMANCE Thermoplastic polyimide products offer the design engineer practical, cost-competitive solutions to difficult problems in high temperature applications. Vespel TP-8 Series parts are specified in high performing applications where thermal stability, electrical properties, wear and friction behavior are required in mechanical components that are designed to accommodate injection molding or other melt-processing technologies. Today s competitive markets place a premium on the role of the design engineer, both in designing new products and redesigning existing ones. Therefore, the intent of this manual is to provide assistance to designers, during selection, testing and specification of Vespel TP-8 Series parts. This design manual contains comprehensive physical property and performance data on the TP-8 Series resins. All of the data in the sections that follow are the result of physical property testing conducted by DuPont or its partners. The selection of data for this manual has been made in consultation with design engineers responsible for DuPont Vespel TP-8 Series applications. End-use testing is always recommended.
Table of Contents Page Introduction Fabrication Methods Defining the End-Use Requirements Prototyping the Design Machining from Rod or Plaque Stock Prototype Tool Preproduction Tool Testing the Design Writing Meaningful Specifications Performance Properties 3 Mechanical Properties 3 Thermal Properties 3 Dynamic Mechanical Analysis 3 Thermal Aging 6 Flexural Creep 6 Flexural Fatigue 7 Tribological Properties 7 Electrical Properties 8 Environmental Properties 9 Chemical Exposure 9 Radiation Exposure Outgassing Performance Appendices A Design Check List B Stress/Strain Curves as a Function of Temperature in Tension and Compression C Flexural Creep 4 D Chemical Resistance Data 5 List of Tables Page. Vespel TP-8 Series Overview. Typical Properties (English Units) 4 3. Typical Properties (SI Units) 5 4. Suzuki Thrust Wear Test Results Dry 7 5. Suzuki Thrust Wear Test Results Lubricated 8 6. Dielectric Constant/Dissipation Factor and Dielectric Strength 8 7. Surface and Volume Resistivity 8 8. TP-854 Chemical Resistance Day Immersion 9 9. TP-854 Chemical Resistance 3 Day Immersion 9. Property Retention after Oil Exposure at Elevated Temperature. Property Retention of TP-854 Film after Fuel or Oil Exposure. Outgassing Performance Data List of Figures Page. Tensile Strength as a Function of Temperature 3. Flexural Strength as a Function of Temperature 3 3. Compression Strength as a Function of Temperature 3 4. DMA Curve for TP-854 6 5. DMA Curve for TP-83 6 6. Tensile Strength Retention of TP-854 after Aging 6 7. Elongation Retention of TP-854 after Aging 6 8. Flexural Creep 7 9. Flexural Fatigue 7. Suzuki Thrust Wear Test Schematic 7. Dielectric Strength IEC 643 8. Dissipation Factor IEC 65 8 3. Dielectric Constant IEC 65 8 4. Vespel TP-8556 Tensile Strength and Notched Charpy Impact Performance After Aging Exposure in B ATF Fluid A- Design Check List B- TP-854 Stress/Strain in Tension B- TP-8395 Stress/Strain in Tension B-3 TP-8 Stress/Strain in Tension B-4 TP-83 Stress/Strain in Tension B-5 TP-83 Stress/Strain in Tension B-6 TP-8549 Stress/Strain in Tension B-7 TP-879 Stress/Strain in Tension B-8 TP-854 Stress/Strain in Compression 3 B-9 TP-8395 Stress/Strain in Compression 3 B- TP-8 Stress/Strain in Compression 3 B- TP-83 Stress/Strain in Compression 3 B- TP-83 Stress/Strain in Compression 3 B-3 TP-8549 Stress/Strain in Compression 3 B-4 TP-879 Stress/Strain in Compression 3 C- TP-854 Flexural Creep 4 C- TP-8395 Flexural Creep 4 C-3 TP-8 Flexural Creep 4 C-4 TP-83 Flexural Creep 4 C-5 TP-83 Flexural Creep 4 C-6 TP-8549 Flexural Creep 4 C-7 TP-879 Flexural Creep 4 D Chemical Resistance Data for TP-854 Film 5
INTRODUCTION DuPont Vespel TP-8 series of products are primarily semicrystalline polyimide having a Tg of 5 C (48 F) and a Tm of 388 C (73 F). However, the molded products are amorphous because the crystallization speed is slower than that of typical semi-crystalline polymers. TP-8 can be used up to 4 C (464 F) in the as-molded amorphous state; however, it can be used above 4 C up to 3 C (68 F) when crystallized after molding. Contact DuPont for information on amorphous grades. The TP-8 series includes several different products that cover a wide array of high temperature and high wear applications. The table below gives a brief overview of the product offering. While this design manual covers several TP-8 grades, specialty grades are also available. Fabrication Methods Because TP-8 series products are thermoplastic, they can be fabricated into articles using melt processing techniques such as injection molding, extrusion, and thermoforming. This processing flexibility gives design engineers increased geometric options to creatively solve design problems without the added cost of a secondary machining operation. Furthermore, given the geometric flexibility that comes with these processes, multiple components may be incorporated into a single part, reducing tooling, inventory and part handling costs. When metal or ceramic mating components are required, insert-molding Vespel TP is an option, adding more design flexibility and overall part functionality. Defining the End-Use Requirements The most important first step in designing a plastic part is to define properly and completely the environment in which the part will operate. Properties of plastic materials are substantially altered by temperature, chemical exposure, and applied stress. These environmental effects must be defined on the basis of both short and long term exposure conditions. Time under stress and environment is important in determining the extent to which properties, and thus the performance of the part will be affected. If a part is to be subject to temperature changes in the end-use, it is not enough to define the maximum temperature to which the part will be exposed. The total time the part will be at that temperature during the design life of the device must also be calculated. The same applies to stress resulting from an applied load. If the stress is applied intermittently, the time it is applied and the frequency of occurrence is important. Plastic materials are subject to creep under applied stress and the creep rate is accelerated with increasing temperature. If loading is intermittent, whether or not the plastic part recovers depends upon the stress level, the duration of time the stress is applied, the length of time the stress is removed or reduced, and the temperature during each time period. The effect of chemicals, lubricants, and other agents is likewise time and stress dependent. Some materials may not be affected in the unstressed state, but will stress crack when stressed and exposed to the same reagent over a period of time. A design checklist is included in Appendix A to serve as a guide when defining the end-use requirements. Table Vespel TP-8 Series Overview Vespel TP Grade Nominal Composition Performance Overview Typical Applications TP-854 TP-8395 TP-8 TP-83 Unfilled PTFE, Filler Blend Glass Fiber Filled Carbon Fiber Filled, Lubricated General purpose unfilled grade used in insulating applications. Used for wear applications where the countersurface is highly polished or a soft metal. High modulus grade used in insulating applications that do not require wear resistance (Glass is aggressive towards countersurface). Internally lubricated, high modulus grade used in both dry and lubricated wear environments. Electrical bushings, thermal and electrical Insulator rings and pads, connectors, switches Wear rings, washers, seal rings Brackets, thermal and electrical insulators Thrust washers, bushings bearings, wear pads and strips TP-83 Carbon Fiber Filled, Lubricated Medium modulus grade used in both dry and lubricated wear environments. Fairings, wear strips and pads TP-8549 Carbon Fiber Filled, Lubricated High modulus grade similar to TP-83 but offers improved wear performance and chemical resistance. Thrust washers, bushings bearings, wear pads and strips TP-879 TP-8556 Carbon Fiber Filled, PTFE Filled Carbon Fiber Filled, PTFE, Filler Blend Similar in strength to TP-83 with better wear resistance at high speeds in lubricated environments. Similar to TP-879 but with better dimensional stability. Seal rings, piston rings, vanes Seal rings, thrust washers
Prototyping the Design In order to move a part from the design stage to commercial reality, it is often necessary to produce prototype parts for testing and modification. The preferred method for making prototypes is to simulate as closely as practical the same process by which the parts will be made in commercial production. The discussion that follows will describe the various methods used for making prototypes, together with their advantages and disadvantages. Machining from Rod or Plaque Stock This method is commonly used where the design is very conceptual and only a small number of prototypes are required, and where relatively simple part geometry is involved. Machining of complex shapes can be expensive, but machined parts can be used to help refine part design. Machined prototypes are not recommended for final evaluation prior to commercialization. The reasons are as follows: Properties such as strength, toughness and elongation may be lower than that of the molded part because of machine tool marks on the machined prototype. If fiber reinforced resin is required, the effects of fiber orientation can differ. It is common for machined parts from fiber filled product to have less than half the strength than that in molded form. Furthermore, if machined parts will be used for wear testing, the exposed fiber ends for fiber filled resins might lead to different results versus actual performance from a molded article. Surface characteristics such as knockout pin marks, gate marks and mold parting line found in molded parts will not be represented in the machined part. The effect of knit lines in molded parts cannot be studied in a machined prototype. Dimensional stability may be misleading due to differences in internal stresses and fiber orientation, if fiber reinforced products are used. Density gradient or voids often found in the center of thick rod and plaque stock can reduce part strength. Likewise, the effect of voids sometimes present in thick sections of a molded part cannot be evaluated. There may be a limited selection of resins available in rod or plaque stock. Prototype Tool A better alternative to machined prototypes is to mold the part in a prototype tool. This approach better simulates a production molded part. Basic information will then be available to account for mold shrinkage, fiber orientation and gate position. This type of tool will provide parts which are more suitable for end-use testing. Prototype mold tools can potentially be modified to accommodate changes in geometry and dimensions. Prototype tools have a limited life and should not be used to support commercial production. Preproduction Tool The best approach for precision parts is the construction of a preproduction tool. This can be a single cavity mold, or a single cavity in a multi-cavity mold base. The cavity will have been machine finished but not hardened, and therefore some alterations can still be made. It will have the same cooling as the production tool so that any problems related to warpage and shrinkage can be studied. With the proper knockout pins, the mold can be cycled as though on a production line so that cycle times can be established. Most importantly, parts can be evaluated for dimensions and geometry, strength, impact, wear, and other physical properties in the actual or simulated end-use environment. Testing the Design Every design should be thoroughly tested while still in the prototype stage. Early analysis of design options and validations of assumptions will save time, labor, and material. The following are general options for validating the final design: Actual end-use testing is the best test of the prototype part. All performance requirements are encountered here, and a complete evaluation of the design can be made. Simulated service tests can be conducted. The value of such tests depends on how closely end-use conditions are duplicated. For example, an under hood automotive part might be given temperature, vibration and hydrocarbon resistance tests; a bracket might be subjected to abrasion and impact tests; and an electronic component might undergo tests for electrical and thermal insulation. Field testing is highly recommended. However, long-term field or end-use testing to evaluate the important effects of time under load and temperature is sometimes impractical or uneconomical. Accelerated test programs permit long-term performance predictions based upon short term severe tests; but good judgment is necessary. The relationship between long versus short term accelerated testing is not always known. Your DuPont representative should be consulted when accelerated testing is contemplated. Writing Meaningful Specifications A specification is intended to satisfy functional, aesthetic and economic requirements by controlling variations in the final product. The designers specifications should be clear, consistent and exact reasonable tolerances. Specifications should outline the following part attributes: Desired parting line locations and allowable mismatch Flash limitations
Permissible gating and knit line areas (away from critical stress points) Permissible knockout pin locations and allowable mismatch Location where voids and sink are intolerable Allowable warpage Tolerances Part marking technique and location As-molded versus machined surfaces Cleaning and packaging requirements Specify Vespel TP family PERFORMANCE PROPERTIES DuPont Vespel TP-8 Series products are near the top of the engineering polymers performance pyramid. The following sections will illustrate the capability of these products across a broad temperature range and demonstrate their potential use in a wide variety of demanding applications. Typical properties are summarized in Tables and 3. Mechanical Properties Vespel TP-8 series products offer excellent mechanical performance in demanding environments, particularly at high temperature. These products are candidates for fabrication of components used in elevated temperature environments. Figures 3 show mechanical performance across a broad temperature range. TP-8 retains significant strength even at temperatures as high as 5 C (3 F), beyond the capabilities of many other thermoplastic materials. Since designers also are interested in the stress-strain behavior, stress-strain curves for each grade in tension and compression are provided in Appendix B. Thermal Properties Dynamic Mechanical Analysis (DMA) Although heat deflection temperature (HDT) is an indicator of how a material will perform at elevated temperatures, DMA offers more insight into how a material might respond in a given environment. DMA provides valuable data for characterizing the thermal performance of polymers. DMA measures the amplitude and phase of a sample s displacement in response to an applied oscillating force. The stiffness of the sample is calculated from this data and converted to a modulus to enable inter-sample comparison. Tan δ, the loss tangent or damping factor, is also calculated. A temperature scan at constant frequency can generate a fingerprint of the material s relaxational processes and its glass transition temperature (T g). Figure. Tensile Strength as a Function of Temperature (ISO 57) Tensile Strength, MPa Temperature, F 58 3 3 39 3 43.5 5 5 5 5 5 5 Temperature, C TP-854 TP-8395 TP-8 TP-83 TP-83 TP-8549 TP-879 36.5.75 4.5 Figure. Flexural Strength as a Function of Temperature (ISO 78) Flexural Strength, MPa 3 68 4 4 76 48 84 3 4 58. 35 3 5 5 Temperature, F 5 7.5 4 6 8 4 6 Temperature, C TP-854 TP-8395 TP-8 TP-83 TP-83 TP-8549 TP-879 Figure 3. Compression Strength as a Function of Temperature (ISO 64) Compression Strength, MPa 3 5 5 Temperature, F 9. 7.5 5.76 43.5 36.5 9..75 4.5 3 68 4 4 76 48 84 3 35 5.76 4.5 4 6 8 4 6 Temperature, C 43.5 36.5 9..75 Tensile Strength, ksi Flexural Strength, ksi Compression Strength, ksi TP-854 TP-8395 TP-8 TP-83 TP-83 TP-8549 TP-879 3
Table Typical Properties (English Units) Properties Test Method Units TP-854 TP-8395 TP-8 TP-83 TP-83 TP-8549 TP-879 TP-8556 Mechanical Tensile Strength, 4 F 73 F F 3 F ISO 57 kpsi 5.4.3 7.3 7..5 9.9 7. 5.5 3..3 4. 4. 3.4 9.5 3. 9. 35. 5.3.9 8.4 37.3 3..3. 8. 6..5 8.3.6 5.4 Tensile Elongation, 4 F 73 F F 3 F ISO 57 % 3 9 94 9 4 7 8 Tensile Modulus, 4 F 73 F F 3 F ISO 57 kpsi 63 8 9 3 75 5 7,49,49 943 865 3,78 3,6 3,7 3,5 4,,6,56,93 3,9 3,53 3,3,77,,4,3,6 Flexural Strength, 3 F 73 F 3 F ISO 78 kpsi 9.9.8 7. 35. 5. 5.3 48.7 3.9 39.6 37.5 7.7 55. 5.9 3.8 4.6 4.3 8.7 6.4 8.9 Flexural Modulus, 3 F 73 F 3 F ISO 78 kpsi 47 37 377,4, 3, 3,54,854,43,5,39 3,48 3,4,774,96,47,96,4,47 Compressive Strength, 3 F 73 F 3 F ISO 64 kpsi 37..3 33.8.9 48. 3. 44.8 45. 3. 33. 3.8.6 44. 44.4 7.7 9.4 9.7. 3.6 Compressive Modulus, 3 F 73 F 3 F ISO 64 kpsi 97 66 97 8 39 365 4 445 434 348 43 365 46 47 388 43 387 389 Izod Impact Strength ASTM D56 ft-lbs/in notched.7.5...8... Poisson s Ratio.34.9.3.45.43.48.46 Thermal Deflection Temperature Under Load, 64 psi Coefficient of Linear Thermal Expansion Flow Direction Cross-Flow Direction ASTM D648 F ASTM E8 73 3 F 5 in/ in/ F 46 446 475 475 475 46 475 47.7.9.7.9 Thermal Conductivity ASTM C77.3 4.5 Specific Heat DSC BTU/lb F 73 F F 57 F.4.4.34.3.3.3 Electrical Dielectric Constant Dissipation Factor khz MHz khz MHz IEC 65 IEC 65.9.9..6 3. 3...6 Dielectric Strength IEC 643 kv/mm 3.9 8.3 3.3 Surface Resistivity IEC 693 Ohm/Sq 5.E+7 3.3E+6.4E+7.8E+6.7E+4 8.4E+6 3.9E+ Volume Resistivity IEC 693 Ohm-cm 5.E+7 8.7E+7 9.E+6.4E+6.3E+5.E+7.E+ General Specific Gravity ASTM D 79.33.38.56.43.35.4.46.46 Water Absorption, 4 hr at 73 F ASTM D 57 %.34..3.3.3.8...9.9 3.4 3.3..6.3.6.6 43. 3.796..9.8 6.7 6..39.9.6. 7. 34.3.54.6.3.9 8. 3..6.6.4. 4
Table 3 Typical Properties (SI Units) Mechanical Properties Test Method Units TP-854 TP-8395 TP-8 TP-83 TP-83 TP-8549 TP-879 TP-8556 Tensile Strength, 4 C 3 C C 5 C Tensile Elongation, 4 C 3 C C 5 C Tensile Modulus, 4 C 3 C C 5 C Flexural Strength, C 3 C 5 C Flexural Modulus, C 3 C 5 C Compressive Strength, C 3 C 5 C Compressive Modulus, C 3 C 5 C Izod Impact Strength notched ISO 57 MPa 6 85 5 48 ISO 57 % 3 9 94 ISO 57 MPa,5, 74 6 ISO 78 MPa 37 88 ISO 78 MPa,94,549 ISO 64 ISO 64 MPa MPa 56 54 358 44 86 68 48 38 9 4 7 8,47,,4 84 7,598 33 44 358 54 58 47 98 96,, 6,5 6, 4 7 9,646 8,68 33 695 56 3 3 6 3 6,,5,9, 353 336 7,67,4 9,664 39 3 86 368 99 43 74 44 7 8,3,,7 3,3 73 58 9 9,853,349 9,584 9 9 49 399 847 56 57 8 54 38 7, 4,3,8 9, 38 358,69,648 9,3 35 36 9 937 875 675 94 8 55 6 4,4 6,6 5,4 4,9 94 78 98 3,54 4,4 3,7 ASTM D56 J/m 9.8 8. 7.5 96 6 Poisson s Ratio.34.9.3.45.43.48.46 Thermal Deflection Temperature Under Load,.8 MPa Coefficient of Linear Thermal Expansion Flow Direction Cross-Flow Direction ASTM D648 C ASTM E8 5 cm/ cm/ C 3 5 45 778 668 68 4 6 8 3 9653 35 38 3 46 46 46 39 46 44 4.9 5. Thermal Conductivity ASTM C77 W/m K.7.34 Specific Heat DSC kj/ C kg 3 C C 3 C....96.96.3 Electrical Dielectric Constant Dissipation Factor khz MHz khz MHz IEC 65 IEC 65.9.9..6 4.9 5. 3. 3...6 Dielectric Strength IEC 643 kv/mm 3.9 8.3 3.3 Surface Resistivity IEC 693 Ohm/sq 5.E+7 3.3E+6.4E+7.8E+6.7E+4 8.4E+6 3.9E+ Volume Resistivity IEC 693 Ohm-cm 5.E+7 8.7E+7 9.E+6.4E+6.3E+5.E+7.E+ General Specific Gravity ASTM D 79.33.38.56.43.35.4.46.46 Water Absorption, 4 hr at 3 C ASTM D 57 %.34..3.3.3.8...6 5. 3.4 3.3..6.5 4.7.6 43. 3.796..6 5. 6.7 6..39.9. 3.6 7. 34.3.54.6.5 5. 8. 3..6.6 63.7 3.6 5
Figures 4 and 5 show the DMA results for TP-854 and TP-83, respectively. These curves are most helpful to designers seeking to identify the T g and understand the stiffness behavior of a component as temperature changes. The DMA curve provides the designer a better understanding of the dimensional stability and retention of mechanical propeties of precision parts, especially at elevated temperatures. Thermal Aging TP-8 Series resins offer long-term thermal stability at elevated temperatures. To help illustrate this performance, test specimens were aged at C (39 F) for 5 hours while monitoring their tensile strength and elongation retention. Figure 6 shows retention of tensile strength even after 5 hr at C (39 F). Figure 7 shows a significant retention of elongation after the same period. Figure 6. Tensile Strength Retention of TP-854 after Aging at C (39 F) (ISO 57) Tensile Strength Retention, %.. 8. 3 4 5 6 Hours Figure 4. DMA Curve for TP-854 Figure 7. Elongation Retention of TP-854 after Aging at C (39 F) (ISO 57) Storage Modulus, MPa 3 5 5 Temperature, F 3 3 39 48 57 66 5. C 5 MPa. Hz 35.43 C 33. MPa. Hz 5.3 C.46. Hz Tan Delta.5..5 4 3 Loss Modulus, MPa Elongation Retention, %.. 8. 5 5.5 C.635 MPa. Hz. 6. 3 4 5 6 Hours 5 5 5 3 Temperature, C 35 Flexural Creep Figure 5. DMA Curve for TP-83 Storage Modulus (MPa) 8 6 4 DMA Multi-Frequency - Dual Cantilever 5. C 9953MPa Hz DMA 38.6 C 845MPa Hz 46.9 C.88 Hz 7.77 C.666 Hz Tan Delta.8.6.4. 5 5 Loss Modulus (MPa) Plastics tend to deform over time when exposed to a sustained load. This is known as creep. The designer should account for creep in applications where the components are exposed to a long-term load. Like other performance attributes, creep will be influenced by the magnitude of the applied load as well as the temperature at which the load is applied. The flexural creep performance for TP-8 products at 3 C (73 F) and 48 MPa (7, psi) is shown in Figure 8. Typically, unfilled or lightly filled products will exhibit higher initial strain and creep, as seen here. Appendix C contains flexural creep data for select grades at elevated temperature.. Temperature ( C) 3 4 Universal V3.9A TA Instruments 6
Figure 8. Flexural Creep at 3 C (73 F)/48 MPa (7, psi) (ASTM D 99) 3.5.5 % Strain.5.. Hours Flexural Fatigue TP-8395 TP-854 TP-83 TP-8 TP-83 TP-8549 TP-879 Some applications stress components by cyclical loading or vibration. Flexural, compressive, shear (twist) or tensile loading may result. Repeated cyclic loading causes a deterioration of mechanical performance and potentially leads to complete failure. Fatigue resistance data is important to designers for any part that will be used in an application that involves cyclic loading such as gears, rollers or components in vibrating equipment. Figure 9 shows the flexural fatigue performance of select TP-8 grades. Tribological Properties One of the main performance attributes of DuPont Vespel TP-8 Series products is their wear and friction behavior. Wear and friction performance is not a material attribute, but a system property resulting from the interaction of two materials at specific conditions. Factors such as load, velocity, dry or lubricated environment, countersurface composition, surface finish and temperature all contribute to wear and friction performance. To give an indication of wear performance, certain TP-8 grades were tested under thrust wear conditions. Results are shown in Tables 4 and 5. The test is based upon the Suzuki thrust wear method (JIS-K78A) as shown in Figure. The washers did not contain grooves. Dry wear testing was conducted over a 7 hour period while lubricated testing was conducted over a 4 hour period. The countersurface was 34 stainless steel. This countersurface material corresponds to ANSI 34 and ISO 683/3. Generally, the highly loaded carbon fiber grades tend to perform well under high loads, and low speed. Grades containing PTFE, or PTFE and carbon fiber tend to perform well under high speeds, and low load. Because grade selection will depend on many factors, please consult with a Vespel Technical Service Representative for assistance in selecting the appropriate grade for your application. Figure. Suzuki Thrust Wear Test Schematic (JIS-K78A) Figure 9. Flexural Fatigue at 75 khz (ASTM D 67) Weight (Constant) 6 8.7 Test Piece (Fixed Cylinder) 5 7.5 Slide Surface Maximum Strength, MPa 4 3 5.8 4.35.9.45 Maximum Strength, ksi Heating of Total Enviroment Friction Material (Rotary Plate),,,,,, Cycles to Failure TP-854 TP-8395 TP-83 Grade Table 4 Suzuki Thrust Wear Test Results Dry PV psi ft/min PV MPa m/s friction, µ wear factor, K - cm 3 /kgfm resin wear, mg metal wear, mg TP-83 7,.5.5 66 < TP-83 95, 3.3.4 77 6 < TP-8549 7,.5.5 49 9 < TP-8549 95, 3.3.5 63 4 < TP-83 4,.5. 67 3 < TP-83 8,.. 49 34 < 7
Grade Table 5 Suzuki Thrust Wear Test Results Lubricated PV psi ft/min PV MPa m/s friction, µ wear factor, units resin wear, mg metal wear, mg TP-83 98,.4.3 4 < TP-83 357,.5.3 3 < TP-8549 98,.4. 3 < TP-8549 357,.5. 4 < TP-83 98,.4. 3 < TP-83 357,.5. < TP-8549 98,.4.3 3 < Figure. Dissipation Factor IEC 65 ( mm, 5% RH, khz) DF.5.4.3.. Vespel TP-854 4 6 8 4 6 8 Temperature Vespel TP-8 Electrical Properties The unfilled and glass filled TP-8 grades are excellent electrical insulators. The dielectric constant, dissipation factor and dielectric strength for the insulating TP grades are listed in Figures 3 and Table 6. Table 7 lists the surface and volume resistivities. Figure 3. Dielectric Constant IEC 65 ( mm, 5% RH, kv/s, Ball in Oil) DC 4 3.5 Vespel TP-854 Vespel TP-8 Figure. Dielectric Strength IEC 643 ( mm, 5% RH, kv/s, Ball in Oil) 3 4 6 8 4 6 8 Temperature 6 Vespel TP-854 Vespel TP-8 DS (kv/mm) 5 4 3 4 6 8 4 6 8 Temperature Table 6 Dielectric Constant/Dissipation Factor and Dielectric Strength (3 C [73 F],. mm [.797 inch] Thickness) Dielectric Contant (IEC 65) Dissipation Factor (IEC 65) Dielectric Strength (IEC 643) khz MHz khz MHz kv/mm TP-854.9.8..6 3.9 TP-8 3.4 3.3..6 3.3 Table 7 Surface and Volume Resistivity Surface Resistivity (IEC 693) Ohm/sq Volume Resistivity (IEC 693) Ohm-cm TP-854 5.E+7 5.E+7 TP-8395 3.3E+6 8.7E+7 TP-8.4E+7 9.E+6 TP-83.8E+6.4E+6 TP-83.7E+4.3E+5 TP-8549 8.4E+6.E+7 TP-879 3.9E+.E+ 8
Environmental Properties Chemical Exposure DuPont Vespel TP-8 Series parts are processed from a chemically resistant advanced engineering thermoplastic. They offer resistance against many acids, bases, and organic solvents. Solvents Organic solvents in general have little effect on the mechanical and dimensional stability of polyimide parts. Chlorinated and fluorinated solvents such as perchloroethylene and trichloroethylene are recommended for surface cleaning of Vespel parts. Hydrocarbon solvents such as toluene and kerosene have virtually no effect on polyimide materials. At high temperatures, some solvents containing functional groups such as m-cresol and nitrobenzene can cause swelling of polyimides without substantially reducing its mechanical strength. Acids Concentrated mineral acids cause severe embrittlement of polyimide parts in a relatively short time and should be avoided. Generally, dilute acid solutions and aqueous solutions of inorganic salts having acidic ph s have about the same effect on polyimide as water. Bases Generally, polyimide resins are susceptible to alkaline attack. Aqueous bases attack polyimides leading to rapid deterioration of properties. All basic solutions with a ph of or greater, including salt solutions, should be avoided. Cleaning agents of a caustic nature are not recommended. Certain grades of TP-8 can be annealed to induce crystallization and further reduce sensitivity to chemicals such as nitric acid and dichloromethane. Tables 8 and 9 show the chemical resistance of TP-854 test specimens when immersed in a wide variety of chemical substances. Additional chemical resistance data for test specimens and films of TP-854 can be found in Appendix D. Speciality grades of Vespel may offer higher chemical resistance if needed. Contact DuPont for more information. Table 8 TP-854 Chemical Resistance Day Immersion at 3 C (73 F) Appearance After Exposure Amorphous Crystalline Hydrochloric Acid % Solution Concentrate Sulfuric Acid 35% Solution Concentrate Swelling Nitric Acid 35% Solution Concentrate Swelling Slight Craze Soldium Hydroxide % Solution 4% Solution Potassium Hydroxide % Solution 4% Solution Swelling Slight Craze Engine Oil Gear Oil Toluene Perchloroethylene Tricholorethylene Dichloromethane Slight Craze Chloroform Slight Craze Gasoline Kerosene Table 9 TP-854 Chemical Resistance 3 Day Immersion Appearance After Exposure Amorphous Crystalline Methyl ethyl ketone 3 C (73 F) Skydrol (#5b-4) 3 C (73 F) Skydrol (#5b-4) 8 C (76 F) Fluid Exposure DuPont Vespel TP-8 Series products exhibit resistance against some common fluids at elevated temperatures. TP-854 shows outstanding retention of properties and appearance when a test specimen is immersed in common oils and fuels such as engine oils, gear oils, brake fluids, sour oils, synthetic fuels, and gasohol, even at elevated temperatures. (See Tables.) Skydrol is a registered trademark of Solutia, Inc. 9
Table Property Retention After Oil Exposure at Elevated Temperature TP-854 Test Specimen Exposure Test Method Engine Oil at 7 Days C (39 F) Gear Oil at 7 Days C (39 F) Tensile Strength at Yield ASTM D638 Tensile Strength at Break ASTM D638 9 95 Elongation at Break ASTM D638 9 Flexural Strength ASTM D79 5 Flexural Modulus ASTM D79 Weight Change ASTM D543 +. +.6 Appearance Engine Oil: Toyota Castle Motor-oil Clean Royal II (7.5W 3SE) Gear Oil: Toyota High-point Gear Oil (85W-9) Property Retention, % Figure 4 shows that Vespel TP-8556 maintains critical mechanical performance of tensile strength and notched izod impact strength even after 3 hr exposure to -B automatic transmission fluid (ATF) at 5 C. Figure 4. Vespel TP-8556 Tensile Strength and Notched Charpy Impact Performance After Aging Exposure in B ATF Fluid (ASTM D543) Tensile Strength (MPa) 6. 4... 8. 6. Ult. Tensile Strength Fluid Aging at 3 C) Notched Charpy Impact Fluid Aging at 3 C) Tensile ISO 57- Notched ISO 79-eA Charpy Ult. Tensile Strength Fluid Aging at 5 C) Notched Charpy Impact Fluid Aging at 5 C) 8. 7. 6. 5. 4. 3. Notched Izod Impact (J/m) 4.. Table Property Retention of TP-854 Film After Fuel or Oil Exposure TP-854 Film Exposure (3 C) Property Retention, % at 3 C (73 F) Brake Oil Synthetic Fuel Oil hr hr hr hr Tensile Strength at Yield 5 5 Tensile Strength at Break 95 95 95 Appearance Brake Oil: Brake Fluid DOT 3 of Nippon Petroleum Company Synthetic Fuel Oil: Toluene/iso-octane 6/4 volume % TP-854 Film Exposure (3 C) Property Retention, % at 3 C (73 F) Sour Oil Gasahol hr hr hr hr Tensile Strength at Yield 5 5 Tensile Strength at Break 95 5 5 Appearance Sour Oil: Synthetic Fuel Oil/lauroyl peroxide /5 weight % Gasahol: Synthetic Fuel Oil/methanol / volume % TP-854 Film Exposure (8 C) Property Retention, % at 8 C (356 F) Gear Oil 5 hr hr hr Tensile Strength at Yield Tensile Strength at Break 95 9 5 Appearance Gear Oil: Showa white pilot S-3 (W-3).. 5 5 5 Exposure Time (hr) Radiation Exposure Table Outgassing Performance Data (ASTM E-595) Grade TML, % CVCM, % WVR, % TP-854.587.4.39 TP-8.4.8.7 TML : Total Mass Loss CVCM: Collected Volatile Condensable Materials WVR: Water Vapor Regained Conditions: Vacuum: 5 x 5 torr Heating Element Temperature: 5± C (34 F) Cooling Element Temperature: 5± C (34 F) Duration: 4 hr.. 3 When polymers are used as insulation materials for atomic power plants or aerospace applications, radiation resistance may be an important property. When plastics are irradiated, inter-polymer cross-linking and breakage of the polymer chain may take place simultaneously. According to the extent of these phenomena, polymers may be classified into cross-linking and breakage types. Contact DuPont for further information on radiation exposure and for any potential applications in military, medical, and atomic power application. Outgassing Performance Certain TP-8 grades offer low outgassing in vacuum environments, making them suitable candidates for clean applications such as semiconductor fabrication and support components. Table shows outgassing results per the ASTM E-595 test protocol.
APPENDICES Appendix A Design Check List Part Name Company Print No. Job No. A. PART FUNCTION B. OPERATING FUNCTIONS Normal Max. Min. Operating temperature Service life (hrs) Applied load (lb torque, etc. describe fully on reverse side) Time on Duration of load Time off Other (Impact, Shock, Stall, etc.) C. ENVIRONMENT Chemical Moisture Ambient temperature while device not operating Sunlight direct Indirect D. DESIGN REQUIREMENTS Factor of safety Max. Deflection/Sag E. WEAR CONSIDERATIONS Mating Material Surface Finish Pressure Velocity Rotation or Oscillation Limiting Wear Rate or Wear Volume F. FORMING CONSIDERATIONS
Appendix B Stress/Strain Curves as a Function of Temperature in Tension and Compression Figure B- TP-854 Stress/Strain in Tension (ISO 57) TP-854 8 6 4 4 C ( 4 F) 3 C (73 F) C ( F) 5 C (35 F) 7.4 4.5.6 8.7 5.8.9 5 5 Figure B- TP-8395 Stress/Strain in Tension (ISO 57) Figure B-3 TP-8 Stress/Strain in Tension (ISO 57) TP-8 8 6. 4 C ( 4 F) 6 3 C (73 F) 3. C ( F) 4 5 C.3 (35 F) 7.4 4.5 8 6 4.6 8.7 5.8.9 3 4 5 TP-8395 8 6 4 4 C ( 4 F) 3 C (73 F) C ( F) 5 C (35 F) 7.4 4.5.6 8.7 5.8.9 5 5 Figure B-4 TP-83 Stress/Strain in Tension (ISO 57) TP-83 3 5 5 5 4 C ( 4 F) 3 C (73 F) C ( F) 5 C (35 F).5..5 Figure B-5 TP-83 Stress/Strain in Tension (ISO 57) TP-83 3 5 5 5.5..5 4 C ( 4 F) 3 C (73 F) C ( F) 5 C (35 F) Figure B-6 TP-8549 Stress/Strain in Tension (ISO 57) TP-8549 3 5 5 5 43.5 36.5 9..75 4.5 7.5 43.5 36.5 9..75 4.5 7.5..5 4 C ( 4 F) 3 C (73 F) C ( F) 5 C (35 F).5..5 Figure B-7 TP-879 Stress/Strain in Tension (ISO 57) TP-879 3 5 5 5 4 C ( 4 F) 3 C (73 F) C ( F) 5 C (35 F).5..5 43.5 36.5 9..75 4.5 7.5 43.5 36.5 9..75 4.5 7.5
Figure B-8 TP-854 Stress/Strain in Compression (ISO 64) Figure B- TP-83 Stress/Strain in Compression (ISO 64) TP-854 35 5.76 3 5 5 5 3 C (73 F) 5 C (35 F) 43.5 36.5 9..75 4.5 7.5 3 4 5 6 TP-83 35 3 5 5 C 5 3 C 5 C 4 6 8 (3 F) (73 F) (35 F) 4 5.76 43.5 36.5 9..75 4.5 7.5 Figure B-9 TP-8395 Stress/Strain in Compression (ISO 64) Figure B-3 TP-8549 Stress/Strain in Compression (ISO 64) TP-8395 35 5.76 3 5 5 5 3 C (73 F) 5 C (35 F) 43.5 36.5 9..75 4.5 7.5 3 4 5 6 TP-8549 35 3 5 5 C 5 3 C 5 C 4 6 8 (3 F) (73 F) (35 F) 4 5.76 43.5 36.5 9..75 4.5 7.5 Figure B- TP-8 Stress/Strain in Compression (ISO 64) TP-8 35 3 5 5 5 4 6 8 3 C (73 F) 5 C (35 F) 4 5.76 43.5 36.5 9..75 4.5 7.5 Figure B-4 TP-879 Stress/Strain in Compression (ISO 64) TP-879 35 3 5 5 C 3 C 5 5 C 4 6 8 (3 F) (73 F) (35 F) 4 5.76 43.5 36.5 9..75 4.5 7.5 Figure B- TP-83 Stress/Strain in Compression (ISO 64) TP-83 35 3 5 5 C 3 C 5 5 C 4 6 8 (3 F) (73 F) (35 F) 5.76 43.5 36.5 9..75 4.5 7.5 4 3
Appendix C Flexural Creep Figure C- TP-854 Flexural Creep (ASTM D99) 3..5..5..5 3 C (73 F)/48 MPa (6.96 ksi) 6 C (4 F)/48 MPa (6.96 ksi) 6 C (4 F)/34 MPa (4.93 ksi).. Time, hr Figure C- TP-8395 Flexural Creep (ASTM D99) 3..5..5 3 C (73 F)/48 MPa (6.96 ksi) 6 C (4 F)/48 MPa (6.96 ksi) 6 C (4 F)/34 MPa (4.93 ksi)..5.. Time, hr Figure C-3 TP-8 Flexural Creep (ASTM D99)..9.8.7.6.5.4.3.. 3 C (73 F)/48 MPa (6.96 ksi) 6 C (4 F)/34 MPa (4.93 ksi) 6 C (4 F)/48 MPa (6.96 ksi).. Time, hr Figure C-4 TP-83 Flexural Creep (ASTM D99)..9.8.7.6.5.4.3.. 3 C (73 F)/48 MPa (6.96 ksi) 6 C (4 F)/34 MPa (4.93 ksi).. Time, hr Figure C-5 TP-83 Flexural Creep (ASTM D99)..9.8.7.6.5.4.3.. 3 C (73 F)/48 MPa (6.96 ksi).. Time, hr Figure C-6 TP-8549 Flexural Creep (ASTM D99)..9.8.7.6.5.4.3.. 3 C (73 F)/48 MPa (6.96 ksi).. Time, hr Figure C-7 TP-879 Flexural Creep (ASTM D99)..9.8.7.6.5.4.3.. 3 C (73 F)/48 MPa (6.96 ksi) 6 C (4 F)/34 MPa (4.93 ksi).. Time, hr 4
Appendix D Chemical Resistance Data for TP-854 Film H SO 4 Property Retention, % at 8 C in H SO 4 Solution ph = ph = 3 hr hr hr hr Tensile Strength at Yield 5 5 Tensile Strength at Break 5 5 Appearance Ozone Property Retention, % at 4 C (4 F) in 5 ppb Ozone Amorphous Crystalline hr hr hr hr Tensile Strength at Yield 5 Tensile Strength at Break 5 Tensile Modulus 5 Elongation at Break 5 5 Appearance HNO 3 / H SO 4 Property Retention, % at 8 C in HNO 3 /H SO 4 Solution ph = ph = 3 hr hr hr hr Tensile Strength at Yield 5 5 5 Tensile Strength at Break 95 95 Appearance NaCl and NaOH Property Retention, % at 3 C (73 F) 5% NaCl 5% NaOH hr hr hr hr Tensile Strength at Yield 5 Tensile Strength at Break 5 9 6 Appearance Methanol and Ethanol Property Retention, % at 3 C (73 F) Methanol Ethanol hr hr hr hr Tensile Strength at Yield Tensile Strength at Break 5 Tensile Modulus 5 5 Elongation at Break 5 5 Appearance Nitric Acid and Phosphoric Acid Tensile Strength at Yield 96 88 Tensile Strength at Break 3 Tensile Modulus 96 65 Elongation at Break +.. Appearance Oil/Refrigerant Property Retention, % 9% Nitric Acid 98% Phosphoric Acid 3 weeks 3 weeks 3 6 C (73 4 F) 3 4 C (73 47 F) Tensile Strength at Yield Tensile Strength at Break Tensile Modulus Elongation at Break 6 Weight Change +. Appearance Property Retention, % Oil/Refrigerant = / wgt Oil: Kyoseki FLEOL F-3 Refrigerant: R-34 A (CH FCF 3) hr at 6 C (4 F) Also considered to have excellent resistance to other refrigerants including, R-3 and R- 5
Visit us at kalrez.dupont.com or vespel.dupont.com Contact DuPont at the following regional locations: North America Latin America Europe, Middle East, Africa 8--8377 +8 7 7 5 +4 77 5 Greater China ASEAN Japan +86-4-885-888 +65-6586-3688 +8-3-55-8484 The information provided in this guide corresponds to our knowledge on the subject at the date of its publication. This information may be subject to revision as new knowledge and experience becomes available. The data provided fall within the normal range of product properties and relate only to the specific material designated; these data may not be valid for such material used in combination with any other materials, additives or pigments or in any process, unless expressly indicated otherwise. The data provided should not be used to establish specification limits or used alone as the basis of design; they are not intended to substitute for any testing you may need to conduct to determine for yourself the suitability of a specific material for your particular purposes. Since DuPont cannot anticipate all variations in actual end-use and disposal conditions, DuPont does not guarantee favorable results, makes no warranties and assumes no liability in connection with any use of this information. All such information is given and accepted at the buyer s risk. It is intended for use by persons having technical skill, at their own discretion and risk. Nothing in this publication is to be considered as a license to operate under or a recommendation to infringe any patent. DuPont advises you to seek independent counsel for a freedom to practice opinion on the intended application or end-use of our products. CAUTION: Do not use DuPont materials in medical applications involving implantation in the human body or contact with internal body fluids or tissues unless the material has been provided from DuPont under a written contract that is consistent with DuPont policy regarding medical applications and expressly acknowledges the contemplated use. For further information, please contact your DuPont representative. You may also request a copy of DuPont POLICY Regarding Medical Applications H-53-5 and DuPont CAUTION Regarding Medical Applications H-5-5. Copyright 5 DuPont. All rights reserved. The DuPont Oval Logo, DuPont, The miracles of science, Kalrez and Vespel are registered trademarks or trademarks of E.I. du Pont de Nemours and Company or its affiliates. VPE-A36--B4 (Previously K-6393-) (7/) Printed in the U.S.A.