MET Essay Example | Topics and Well Written Essays - 250 words - 1

MET - Essay Example A material with a hardness of HRC 40 equals around HB 375, which is considered as moderately hard. Even though this level of hardness is considered suitable, a hardness value of HRC 50 or HB 475 is better when the ductility level is also high which represents about 15% elongation. According to appendix 3, it reveals forms of AISI 1040 and others that are non-listed and oil quenched and they are listed as having adequate hardness levels. Appendix 4-1 indicates the same material that is tempered and quenched in water. The AISI 1040 WQT 700 possesses a hardness of HRC 43 (HB 401), a yield point of 92ksi and elongation percentage of 20. 30. In order to obtain the suitable hardened condition, the whole part is heated and then quenched. The part is hardened the entire time but differs in thick sections. However, no chemical constituent changes are experienced. During the carburizing process, the chemical structure of the surface is altered through carbon infusion. Therefore, the process of carburizing makes the outer surface harder while the inner surface becomes