摘要
通过力学性能实验,金相显微镜和扫描电镜观察显微组织和腐蚀形貌,研究了新型Ni-Cr-Fe镍基合金经热处理后750℃长期时效过程中的力学性能和微观组织行为。结果表明:该合金在750℃长期时效过程中,合金内部析出条状的bcc a-Cr相,并随着保温时间的增加而显著增加。少量α-Cr相析出对合金室温力学性能的影响并不明显。保温2000h后合金的室温塑韧性明显降低,出现韧性/脆性转变。晶界附近体心结构的α-Cr相大量析出是合金的室温塑韧性下降的主要原因,裂纹及二次裂纹易沿α-Cr相扩展。
Through mechanical property experiments,metallographic microscopy and scanning electron microscopy to observe the microstructure and corrosion morphology,the mechanical properties and microstructure behavior of the new Ni-Cr-Fe nickel-based alloy during long-term heat preservation at 750℃after heat treatment were studied.The results show that during the long-term insulation process of the alloy at 750℃,strip-shaped BCC A-Cr phase is precipitated inside the alloy,and it increases significantly with the increase of the holding time.The effect of a small amount ofα-Cr phase precipitation on the mechanical properties of alloy at room temperature is not obvious.After 2000 h of heat preservation,the plastic toughness of the alloy at room temperature is significantly reduced,and the toughness/brittleness transformation occurs.The large number of precipitation of theα-Cr phase of the body center structure near the grain boundary is the main reason for the decrease of the plastic toughness of the alloy at room temperature,and cracks and secondary cracks are easy to propagate along theα-Cr phase.
作者
涂玉国
王华
杨连金
赵衡
薛卫兵
陆吕凯
Tu Yuguo;Wang Hua;Yang Lianjin;Zhao Heng;Xue Weibing;Lu Lvkai(Jiangsu Shenyuan Group Co.,Ltd.,Jiangsu,225722)
出处
《当代化工研究》
2023年第9期42-44,共3页
Modern Chemical Research
关键词
镍基高温合金
时效处理
塑性
Α-CR相
nickel-based high-temperature alloys
aging treatment
plasticity
α-Cr phase
