700 ℃超超臨界鍋爐材料617B合金冷變形和退火過程中的組織演變

700 ℃超超臨界鍋爐材料617B合金冷變形和退火過程中的組織演變Microstructure evolution of alloy 617B for 700 ℃ ultra-supercritical boilers during cold deformation and annealing treatment

冷變形過程對617B合金管材的尺寸精度、組織和性能具有重要影響。通過對617B合金荒管進(jìn)行不同變形量的冷軋實(shí)驗(yàn)，對其冷變形特性進(jìn)行研究。對冷變形后的617B合金進(jìn)行不同制度下的退火處理，對其退火過程中的組織演變規(guī)律進(jìn)行研究，建立退火過程中的再結(jié)晶晶粒長大方程。結(jié)果表明：所構(gòu)建的再結(jié)晶晶粒長大方程與實(shí)驗(yàn)數(shù)據(jù)值吻合度較好；617B合金退火過程中組織均勻性受退火溫度影響最大；由于碳化物條帶的存在，退火過程中易出現(xiàn)組織不均勻的現(xiàn)象，綜合考慮晶粒尺寸和組織均勻性兩個因素最終確定冷軋變形量為20%，中間退火制度為1140 ℃、10 min時得到的組織最為均勻。

Cold deformation has an important effect on the dimensional accuracy, microstructure and mechanical properties of alloy 617B pipes. The cold deformation characteristic of alloy 617B tube was investigated by single-pass cold rolling tests of different deformation degrees. The cold rolled alloy 617B was annealed under different conditions. The microstructure evolution mechanism was investigated, and the equation of recrystallized grain growth during annealing was established. The results shows that the grain size of alloy 617B tends to be uneven as a result of carbide strips. The size of recrystallized grain is mainly controlled by annealing temperature and the grain size predicted by the proposed grain model agrees well with the experimental results. The grain size is mostly uniform when the annealing treatment is (1140 ℃, 10 min) with the cold rolling reduction of 20%.

全文下載：http://pan.baidu.com/s/1o8n0MCy