摘要
通过力学性能试验、光学金相显微镜、透射电子显微镜,研究了HR3C钢焊接接头高温时效后的显微组织和力学性能。试验结果表明,经650℃时效,HR3C钢焊接接头的强度和硬度升高,焊缝硬度上升幅度大于母材;焊缝的时效脆化倾向明显,时效7 000 h后冲击功都保持在15 J以下。对试验结果的分析表明,焊缝区晶界处M23C6相的连续网状分布及σ相、G相的存在导致了其较低的缺口冲击功,而晶内均匀细小Z相的沉淀强化作用则提高了接头的强度和硬度。
Microstructure and mechanical properties of HR3C steel welded joints were studied by mechanical properties tests （MT）, optical microscope （OM） and transmission electron microscope （TEM） after thermal aging. The results showed that the tensile strength and hardness of HR3C welded joints increase after 650 ℃ aging, and the hardness growth of weld is higher than that of base metal. The aging embrittlement tendency of weld is obvious, which keeps at about 15J after aging for 7000 h. The continuous distribution of net-like M23C6 and existence of σ phase and G phase cause lower impact toughness value, while the Z phase precipitation strengthening effect increase the strength and hardness of welded joint.
出处
《焊管》
2013年第9期15-19,共5页
Welded Pipe and Tube
关键词
焊接
HR3C
奥氏体耐热钢
焊接接头
时效脆化
welding
HR3C
autenitic heat resistant steel
welded joint
aging embrittlement
