Tempering and Stabilization:

Tempering of tool steel in heat treatment is again a significant step. The quenching of such steels reasons the existence of untempered martensite, retained austenite and carbide in the structure. This happen due to finer changes in composition does not permit to found correct austenising temperature. Tempering nears removing such structural deficiencies assist also induce secondary hardness. Following figure shows the secondary hardness presence manifested via increased hardness at specific tempering temperature in the condition of high alloy steels. Both intermediate and high alloy steel reduces in hardness respectively upto about 460^oC and 500^oC and thereafter they enhance in hardness. High alloy steels illustrate greatest enhance in hardness along with enhancing tempering temperature.

Figure: Tempering Characteristics of Tool Steels

After tempering primarily the treatment is repeated two or three instance in multi-tempering practice. That treatment stabilizes the microstructure via decreases the amount of retained austenite. Still now another stabilization method is to cool the tempered steel to subzero temperature via placing it in solid carbon dioxide (- 75^oC) or dipping it in liquid nitrogen (- 196^oC).

Normalized quenched, stabilized and tempered tool steel possesses maximum hardness, dimensional stability and wears resistance.

Posted Date: 2/26/2013 6:45:54 AM | Location : United States

Ask an Expert

Related Discussions:- Tempering and stabilization, Assignment Help, Ask Question on Tempering and stabilization, Get Answer, Expert's Help, Tempering and stabilization Discussions

Write discussion on Tempering and stabilization
Your posts are moderated

Write your message here..

Related Questions

Submerged arc welding - set up, SUBMERGED ARC WELDING-Set Up Submerged ar... SUBMERGED ARC WELDING-Set Up Submerged arc welding system consists of the following basic modules: 1. Welding head 2. Power source 3. Flux feeding and recovery units Schematic

Explain different types of frames, (a) Explain different types of frames. C... (a) Explain different types of frames. Compare their merits and demerits. Diagram and illustrate a frameless construction. (b) Illustration briefly the constructional features o

Probability, Airlines like to overbook their flights (this is a vibrant are... Airlines like to overbook their flights (this is a vibrant area of research called yield management). It is estimated that 10% of the people who book their flight do not show up. H

Fluid Mechanics, Please help me solve the following problem. Steam is thro... Please help me solve the following problem. Steam is throttled from a pressure of 700kPa to 100kPa and a temp. of 100 degrees Celsius. Determine the dryness factor of the steam

Annotation with leaders, Annotation with Leaders Ordinate dimensions ar... Annotation with Leaders Ordinate dimensions are not really an dimensions at all in that they do not indicate a measurement.They annotate known as a co-ordinate points. The DIMO

Mechanics of solid, derivation for varing shear stress for thin circular tu... derivation for varing shear stress for thin circular tubes.

Insulation on flanges and valves, Q. Insulation on Flanges and Valves? ... Q. Insulation on Flanges and Valves? Valves, flanges, and unions shall not normally be insulated unless specified by OWNER. All other fittings are to be insulated. Fittings

Describe split pattern or two piece pattern, Split pattern or two piece pat... Split pattern or two piece pattern This is the most widely used type of pattern for intricate castings. When the contour of the casting make sits withdrawal from the mould diff

What do you mean by preignition, Explain the autoignition and detonation th... Explain the autoignition and detonation theory of detonation. What do you mean by preignition ? Describe octane Rating of a fuel. What are the different S.I. engine combustion cham

Determine a static feedforward controller, By operation of the distillation... By operation of the distillation columns you are often interested to maintain output despite fluctuations in the composition, ex. feed composition and feed flow. One possible actua