论文部分内容阅读
本文研究了冷加工对奥氏体型耐热钢ЭИ395及ЭИ69的耐热性能的影响。冷加工采用了冷轧及冷拔两种方法。变形率为25%,50%及75%。首先进行了高温机械性能试验:测定了高温硬度,进行了高温持久强度及在改变应力及温度条件下的高温持久强度试验。结果表示冷加工有效地提高了奥氏体型耐热钢的耐热性能。微观组织及结构的研究证明冷加工所造成的合金的及钢内部的超显微的结构的不均匀状态是合金及钢强化(包括忍热性能)的重要因素。同时由于冷加工所造成的强化相的分析对合金及钢的强化也有很重要意义。ЭИ395及ЭИ69型耐热钢的再结晶的研究说明虽然由于变形率增大而促使易于产生新的再结晶的晶核,但它们的增长速度受变形后特殊结构的影响,因而对耐热钢的耐热性能影响不大。当再结晶晶核的增长速度迅速增大时即消灭了合金及钢中由于冷加工所造成的特殊结构。只有在这样情况下再结晶才减低了合金及钢的耐热性能。
This paper studies the cold working on the heat-resistant properties of austenitic heat-resistant steel ЭИ395 and ЭИ69. Cold-rolled and cold drawn using two methods. Deformation rate of 25%, 50% and 75%. First of all, the high-temperature mechanical properties test was carried out. The high-temperature hardness was measured, the high-temperature permanent strength was tested, and the high-temperature long-term strength test under the condition of changing stress and temperature was carried out. The results show that cold work effectively improves the heat resistance of austenitic heat-resistant steels. Microstructural and structural studies have shown that the non-uniform state of the as-machined microstructures and ultra-microstructures within the steel is an important factor in the strengthening of alloys and steels, including their endothermic properties. At the same time as the analysis of the strengthening phase caused by cold working on the strengthening of the alloy and steel is also very important. The study of the recrystallization of ЭИ395 and ЭИ69 heat-resisting steel shows that although the new recrystallized nuclei are easily produced due to the increase of the deformation rate, their growth rate is affected by the special structure after deformation, Heat resistance has little effect. When the growth rate of recrystallized nuclei increases rapidly, the special structure caused by cold working in the alloy and steel is eliminated. Only in this case recrystallization to reduce the alloy and steel heat resistance.