材料期刊网

在控制的热轧条件下,曾制备了四种不同晶粒大小和显微结构的镇静钢和沸腾钢“钢三”的试样进行了机械时效试验。衡量机械时效处理的后果采用了冲击、抗张、抗压和硬度四种试验。 结果示:控制热轧条件可以改进“钢三”的显微结构,从而改善了“钢三”机械时效处理后的变脆倾向,其中镇静钢的显微结构和晶粒度可以在较大的范围内改变而成品均可以达到标准的要求,但沸腾钢则要严格地控制其显微结构和晶粒度才能合格。 衡量机械时效处理的后果以比较刚性的试验如冲击试验和抗张试验较能给出明确和有规律的结果,抗压度验和硬度试验的结果软不明确而且规律性亦较差。 机械时效处理后的性能的改变是冷加工和时效的综合结果。随着显微结构的不同,冷加工和时效在机械时效处理的总效果中所占的分量亦各异。

Under controlled hot working conditions, the specimens of killed and rimminglow carbon steels having different grain size and microstructure have been prepar-ed and subjected to strain-aging tests. In order to find out the effects of strainingand aging, impact, tensile, compression and hardness tests have been employed. The results show that it is possible to improve the properties of low carbonsteel against straining and aging by controlling the hot working conditions andthat the grain size and microstructure of killed steel may vary within fairly widelimits and yet its impact values after strain-aging may still remain within the re-quired standard; whereas strict control of the grain size and microstructure is ne-cessary in order to produce rimming steel of required impact value after strain-aging. It has been found that the impact and tensile test results show more promi-nently the effects of straining and aging; while the compression and hardness testresults are less consistent and do not yield so clear an information. Straining and aging is the combined effect of cold working and aging. Thecontribution of each of these two factors to the total effect of strain-aging varieswith the microstructure of steel.