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35CrNi3MoAQ钢厚壁管件中存在的白色条带组织是钢锭凝固时,合金元素在晶间偏析,经锻压加工后形成的。条带区富C、Mo、S等,因而硬度高,抗回火,有硫化物夹杂,在一定程度上影响横向断面收缩率。试验证明,条带抗浸蚀,呈白色,是回火不足的表现。加长回火时间哦提高回火温度,条带区碳化物析出增多,抗蚀性降低。高温扩散退火或采用低温浇注,可以减轻或清除条带组织。
35CrNi3MoAQ steel thick-walled tube exists in the white band organization is the ingot solidification, the alloying elements in the intergranular segregation, formed by forging. Strip zone rich C, Mo, S, etc., and thus high hardness, anti-tempering, sulfide inclusions, to a certain extent, affect the transverse section shrinkage. Test proved that the strip resistant to corrosion, was white, is the performance of inadequate tempering. Lengthen the tempering time Oh improve the tempering temperature, strip carbide precipitation increased corrosion resistance decreased. High temperature diffusion annealing or the use of low-temperature casting, can reduce or remove the band organization.