摘要
通过金相组织观察、低温冲击试验和拉伸试验及拉伸断口形貌观察,研究了铌对正火+调质处理低温钢组织及性能的影响。结果表明:铸态下随着试样中铌含量的增加,组织中珠光体片间距逐渐减小,经过930℃正火+900℃淬火+630℃回火热处理后,铌质量分数为0.039%的试样组织及综合性能最佳,组织为回火索氏体,-20、-40℃夏比冲击功分别达到44.4和28.4J,抗拉强度和屈服强度分别为995和885MPa,断后伸长率达到17.0%。
The effect of niobium on microstructure and properties of cryogenic steels was investigated by microstruc ture observation, low-temperature impact toughness test, in this paper. The results show that Nb addition in steels tensile strength test and tensile fracture surface inspection can decrease the lamellar spacing of pearlite as cast. The samples containing 0. 039% Nb have the best microstructure and mechanical properties after normalizing（930 ℃）, quenching（900 ℃） and tempering（630℃ ）. The microstructure is tempered sorbite. The Charpy-V impact energies are 44.4J at -20 ℃ and 28.4J at -40 ℃, respectively, and tensile strength, yield strength and percentage elongation after fracture are 995MPa, 885MPa and 17.0% .
出处
《钢铁》
CAS
CSCD
北大核心
2012年第6期64-68,共5页
Iron and Steel
关键词
低温钢
铌
低温韧性
强度
cryogenic steel
niobium
low temperature toughness
strength
