Metallurgical influence on distortion of the case-hardening steel 20MnCr5

✍ Scribed by C. Prinz; B. Clausen; F. Hoffmann; R. Kohlmann; H.-W. Zoch

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 244 KB
• Volume: 37
• Category: Article
• ISSN: 0933-5137
• DOI: 10.1002/mawe.200500949

✦ Synopsis

In literature, only few works are published that make statements on influences between material properties and distortion. There are some investigations on the influence of carbides and their distribution in the structure. Other authors report on a distinct influence of the texture on distortion. However, the operational sequences during solidification as well as the following deforming processes affect the homogeneity of the chemical composition. Local fluctuations of the chemical composition lead to locally different phase transformations. As a result there will be differences in the structure and therefore inhomogeneous distortion.

The hardenability could be suitable as an integrating parameter to describe the effect of the alloying elements as well as their homogeneity in distribution in the structure on distortion.

Additionally, the preheating treatment of the material as well as the carburizing process can influence the size alteration and the deformation. Therefore, in this work steel of the quality 20MnCr5 with different hardenability grades were varied concerning their preheating treatment conditions. Three conditions were adjusted: annealing to a specific structure, pre-aging and the condition after cooling from the hot rolling heat. The extend of distortion was evaluated by measurements on a coordinate measuring apparatus before and after hardening.