| Cast austenitic stainless steel is widely used for critical components in nuclear power plants. But under the reactor coolant operating temperature (288℃to 327℃), CASS will become thermal ageing embrittlement. Therefore, studying on the cast austenitic stainless steel heat ageing mechanism has important significance. This article systematically analyses macroscopic mechanical properties and microstructure of casting Z3CN20-09M steel which in nuclear power environment for a long time, and summarizes the performance and organizations in the whole process of aging variation, based on these to study the mechanism of heat ageing.The mian job of this article is as follows. First, this paper analyses the microstructure form of Z3CN20-09M steel which after thermal aging, and gets hardness change rule through testing of rockwell hardness and vickers hardness. The second, through the static tensile test and impact test to get the toughness of materials.The reason of toughness is reduced through t statistics test method. Explain the meaning of deformation hardening exponent, and on the basis of tensile deformation to get their change rule.Then, getting the fracture mechanism of Z3CN20-09M steel through analysis of impact fracture and tensile fracture by scanning electron microscopy. The last, having Z3CN20-09M steel thermal aging mechanism through the results of mechanics performance and change rule of the structure. Finally, make recommendations on the service life of pipe by predicting its properties.
|
PDF Full Text Request