Precipitation Hardening Workshet

Worksheet for Jominy End Quench Testing

All work is to be either clearly hand written or typed using 12 point Times New Roman font.Do not go by memory, please use a materials science text (textbook, ASM Handbooks, etc.) and provide bibliography information for sources used (including page numbers).

• On a single graph, plot the hardness as a function of distance from the quenched end for all three steel grades. Be sure to use a format consistent with a report or technical letter (including figure number and caption). Apply a trendline to each dataset (if you are not satisfied with the Excel-generated trendlines, you can ‘freehand’ them instead).The graph should be “stand alone” – the reader should be able to understand the graph and what you are trying to communicate through it by the graph and its caption alone.Attach the original data sheet to the back of this assignment.
• What is meant by “hardness” (define)?
• What is meant by “hardenability” (define)?
• Based on the hardness data you generated for AISI 1045, 4140, and 4340, which grade appears to have the highest hardenability? Which has the lowest hardenability?How do alloying elements such as chromium, molybdenum and nickel increase the hardenability of steel? Note: “hardenability” is NOT the same thing as “hardness”.
• Would you expect the hardness of all three steel grades tested to have similar hardness at the quenched end?Briefly explain why or why not.Do the data confirm your expectation?
• If you needed to fabricate a component that had high hardness values up to 1” below the surface, which alloy would you choose? What is one downside of utilizing a higher-alloyed steel?