Finite element analysis of novel martensitic heat-resistant steel G115 heavy castings

doi:10.13251/j.issn.0254-6051.2022.02.041

Abstract

Abstract: In order to optimize the normalizing and tempering treatment processes of G115 steel thick wall hollow castings, the influence of normalizing and tempering heat treatment process on the temperature field distribution of the casting was analyzed by finite element method. The results show that in the normalizing process, the temperature at the lower edge of the castings is the highest and the heating rate is the fastest, and the inner surface temperature at about 1/4 of the upper end is the lowest and the heating rate is the slowest. In the tempering process, the temperature variation of the castings is similar to that of the normalizing process. The holding time of the lower edge of the castings at the target temperature is the longest, and the holding time at the center of about 1/4 section thickness at the upper end is the shortest. Combined with heating rate, temperature difference, heating efficiency and production cost, normalizing process ② and tempering process ③ are optimized. The microstruture and mechanical properties of the G115 steel casting after heat treating by optimal process are uniform and significantly higher than those of the CB2 steel.

Key words: martensitic heat-resistant steel G115, heavy casting, finite element method, normalizing, tempering

CLC Number:

TG142.1

Zhao Xin, Chen Zhengzong, Zhao Haiping. Finite element analysis of novel martensitic heat-resistant steel G115 heavy castings[J]. Heat Treatment of Metals, 2022, 47(2): 229-235.

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