摘要
为实现油服行业UNS N09925合金的国产化,本研究采用“VIM+VAR”工艺成功冶炼了该合金ϕ508 mm锭,并开展了ϕ228.6 mm(9Inch)锻造棒材的锻造工艺优化试验。为优化锻造加热制度,选用ϕ131 mm锻造棒材为原料研究了热锻态UNS N09925合金从950~1150℃的晶粒度长大规律,试验表明,UNS N09925合金锻材晶粒长大的拐点温度为1020℃,当加热温度达到1100℃以上时,晶粒发生急剧长大。基于锻材晶粒度长大规律,设计采用1120~1160℃和1020~1100℃两组不同的加热制度开展了锻造工艺试验,结果证明,采用1020~1100℃“低温加热”方案生产的两炉ϕ228.6 mm大圆锻材,棒材锻态及固溶态组织最佳,且通过低倍组织、高倍组织、拉伸性能、冲击性能及截面硬度各项试验验证,产品满足API 6A CRA中的各项指标要求,慢应变腐蚀试验TTF比率达到0.88,RA比率达到0.69,满足行业标准中TTF比率≥0.7、RA比率≥0.6的要求。
In order to realize the domestic production of UNS N09925 alloy in the oilfield service industry,the"VIM+VAR"process was successfully used to smelt ϕ508 mm ingot of UNS N09925 alloy,and the forging process optimization test of ϕ228.6 mm(9Inch)forged bar was carried out.In order to optimize the forging heating regime,the grain size growth of UNS N09925 alloy in hot forging state was studied from 950℃ to 1150℃ using ϕ131 mm forging bar as raw material.The experiment shows that the inflection point temperature of grain growth of UNS N09925 alloy is 1020℃.When the heat ing temperature is above 1100℃,the grain grows rapidly.Based on the rule of forging grain size growth,forging process experiments were carried out under two different heating regimes of 1120℃C-1160℃and 1020℃-1100℃.The results showed that the two rods of 228.6 mm large round forging produced by"low temperature heating"at 1020℃-1100℃ had the best microstructure in forged and solid solution state.Moreover,through the tests of low and high microstructure,ten sile properties,impact properties and cross section hardness,the product met the requirements of various indicators in API 6A CRA,and the TTF ratio of slow strain corrosion test reached 0.88 and RA ratio reached 0.69,meeting the re quirements of TTF ratio≥0.7 and RA ratio≥0.6 in the industry standard.
作者
王树财
张佳维
杨亮
于杰
吴银虎
朱玉亮
Wang Shucai;Zhang Jiawei;Yang Liang;Yu Jie;Wu Yinhu;Zhu Yuliang(Fushun Special Steel Co.,Ltd.,Fushun 113001,China;Central Iron&Steel Research Institute Co.,Ltd.,Beijing 100080,China)
出处
《特殊钢》
2025年第5期8-13,共6页
Special Steel
作者简介
王树财(1985-),男,硕士,高级工程师,E-mail:wuli04 hawk@163.com。
