Material Science Engineering and Steel Making/Metallurgy. Stark County High Schools 2016

Transcription

1 Material Science Engineering and Steel Making/Metallurgy Stark County High Schools 2016

2 Agenda What is Material Science Engineering Basics of Steel Making Steel Processing and Properties 2

3 What is Material Science Engineering (MSE) Wikipedia Definition of Material Science: The discovery and design of new materials, incorporates elements of physics, chemistry, and engineering Material scientists emphasize understanding how the history of a material (its processing) influences its structure, and thus the material's properties and performance. Origins of materials science stem from the Enlightenment, when researchers began to use analytical thinking from chemistry, physics, and engineering to understand observations in metallurgy and mineralogy What is was like studying Material Science: Study 3 material types: metals, polymers and ceramics Majority of your study is focused on metals, as metals is the building block for all other materials. Understanding structure, properties and processing of materials Classes: chemistry, math, physics, labs, material science 3

4 Careers in Material Science Engineering Unlimited opportunities Aerospace (Boeing, Nasa, Rolls-Royce) design and material selection for aircrafts and aerospace applications Medical Fields design and material selection of prosthetics, joint replacements, surgical equipment Automotive (GM, Honda) design and material selection for all components of a vehicle Consumer Goods (Food manufacturing) product development, packaging material selection, processing equipment material selection Steel Metallurgy design of new steels, improvement of current steels, failure analysis, material processing & properties optimization 4

5 Metallurgy Summary Processing 5 Structure Properties Performance

6 TimkenSteel - Overview In 1917, the steel business was established within Timken Bearing Company to address supply and quality needs TimkenSteel Corporation became an independent company in 2014 Focus in manufacturing quality steel bars and billets for critical applications Developed precise metallurgical practices and state-of-the-art manufacturing processes We are one of North America s leading producers of large diameter and immediate-size special bar quality (SBQ) steel 6

7 TimkenSteel Where Are We? TimkenSteel Headquarters Harrison Steel Plant 7 Faircrest Steel Plant Gambrinus Steel Plant

8 Agenda What is Material Science Engineering Basics of Steel Making Steel Processing and Properties 8

9 Steel Making Production 1. Melting 2. Refining 3. Casting Bottom Pour = Ingots Strand Cast = Blooms 4. Forge Press Bottom Pour 5. Rolling 6. Piercing (optional) 9

10 Melting Electric Arc Furnace Steel scrap is loaded into the Electric Arc Furnace In 60 minutes the scrap is melted into 175 tons of molten steel 10

11 Refining Vacuum Arc Degasser (VAD) Once the molten steel reached 3000 F the steel is poured into a ladle and transported to the refiner Vacuum Degassing System (Hydrogen Removal) Alloy Addition System (Precise Chemistry Control) Ladle Refining System Reheat System (Precise Temperature Control) Refining / Teeming Ladle 11

12 Casting Bottom Poured Ingots OR Continuous Casting Once refining is complete the ladle is taken to bottom pour which produces steel ingots or to the continuous caster which produces steel blooms. 12

13 Forge Press Some ingots and blooms go through an in-line forge press to improve centerline soundness. 13

14 Rolling Mill The rolling mill controls the shape and size of the steel bar 14

15 Piercing Reheat Pierce Elongate Reduce Size Gage Mill Anneal Hot Bed Cool 15

16 Faircrest Steel Plant Opened in 1985 Located in Canton, OH, USA Capabilities: State-of-art large bar facility EAF - LRS - BP 28 Sq. (711mm) Ingot Finish sizes (140mm 406mm) rds/rcs; 11 x14-3/4 bloom cast 1,000,000+ TPY capacity 16

17 Harrison Steel Plant Opened in 1916 Located in Canton, OH, USA Capabilities: $100 million in upgrades EAF - LRS - bloom cast Finish sizes (25mm 191mm) rds/rcs; round corner squares (81mm to 152 mm) 750,000+ TPY capacity 17 17

18 Gambrinus Steel Plant Opened in 1928 Located in Canton, OH, USA Capabilities: Tube making, thermal treatment, finishing, inspecting and shipping operations One of the most advanced continuous thermal treatment facilities in the world Three tube piercing mills producing products from 1.9 to 13 (48.5mm 330mm) in diameter New intermediate finishing line advances testing quality and reduces processing times 18

19 Agenda What is Material Science Engineering Basics of Steel Making Steel Processing and Properties 19

20 20 Heat Treating

21 Microstructures in Steel Different heat treat recipes result in different structures in steel (microstructures) Different microstructures have different properties We can use microscopy to identify and study the microstructure of different products Microstructure Spherodite Pearlite Bainite Martensite Characteristics Softest structure Good for machining Most stable structure Moderately soft Good ductility Intermediate hardness and strength Maintains ductility Very high hardness and strength Very brittle and no ductility Requires tempering to be useful 21 Martensite Pearlite Spherodite

22 Steel Properties Customers will specify property requirements based off the application Samples are cut from the steel product after heat treat and prepared for various tests Steel properties are measured by a variety of tests Tensile Test Strength Ductility Charpy Impact Toughness Hardness Jominy Test Hardenability 22

23 The Tensile Test Measures: Strength How much stress a material can withstand without deforming Plastic vs elastic deformation Ductility Materials ability to deform when under stresses Material ability to stretch Opposite of brittle Results in a stress strain curve and values for the strength and ductility 23

24 The Stress vs. Strain Curve Measurement of strength: Yield Strength & Ultimate Tensile Strength Measurements of ductility: Elongation & Reduction of Area Elastic Region Once stress is removed returns to original shape and size Plastic Region Permanently deformed by the stress 24

25 25 The Stress vs. Strain Curve

26 The Charpy V Notch Impact Test Measures: Fracture toughness Measure of the amount of energy required to fracture a material that contains a crack The amount of energy required to make a crack grow Usually a reverse relationship between ductility and toughness Testing occurs at various temperatures and results in a plot that shows the toughness at different temperature, as well as the brittle to ductile transition zone 26

27 Charpy V Notch Impact Toughness Charpy Impact Energy (Ft-lbs) Temperature ( o C) Temperature (F) 27

28 Hardness Measures the resistance of a material to deformation due to a constant compression load from an object D Measures the dimensions of an indentation left by a specifically dimensioned and loaded indenter Types: Brinell (1) Rockwell B (2/3) Rockwell C (4/5) 28

29 Jominy Test - Hardenability ALLOY STEEL A measure of the ability for steel to harden in depth Prepare a sample, heat it to hardening temperatures, cool from one end at a controlled rate Measure the hardness variation along the sample HARDNESS Cooling Rate DECREASES Cooling Rate HIGHEST SURFACE CENTER CARBON STEEL CROSS SECTION Hardness DECREASES Hardness HIGHEST SURFACE 29

30 Steel Making Jominy End Quench Curve Steel OIL Q UE NC H.4-.5 H v MILD WATE R Q UE NCH C OOL IN G R AT E 1" 2" 3" 4" 5" 6" 1" 2" 3" 4" 5" 6 " 7" 5 5 F / S 2 5 F / S 12 F / S 7 F /S 290 F /M 2 00 F /M OIL QUE NC H.4-.5 Hv MIL D WATE R QUE NC H C OOLING R AT E 1" 2" 3" 4" 5" 6" 1" 2" 3 " 4" 5" 6" 7" 55 F /S 25 F /S 12 F /S 7 F /S 290 F /M 200 F /M AIR QUENC H BRINELL HARDNESS 3000 KG ROCKWEL L " C" HARDNESS ROC KWELL " B" HARDNESS BRINELL HARDNESS 3000 KG ROC KWELL "C" HARDNESS ROCKWELL "B" HAR DNESS SIXTEENTHS FROM QUENCHED END OF JOMINY BAR ALLOY STEEL SIXTEENTHS FROM QUENCHED END OF JOMINY BAR CARBON STEEL 30

31 Metallurgy Summary Processing 31 Structure Properties Performance

32 32 Discussion