【摘要】 通过末端淬透性试验,研究Nb含量对20CrMnTi钢淬透性的影响。试验结果表明,Nb含量不同的试样,其硬度分布比较接近;硬度曲线上的拐点位置都在5~7 mm处;而且随着距淬火末端距离的不同,其组织变化规律基本相似。由此可见Nb含量不影响20CrMnTi钢的淬透性。Nb对C含量和晶粒度的影响较小,对淬透性的影响较小;固溶的Nb含量很少,不能提高淬透性;Nb的析出相不会促进铁素体形核,不会降低钢的淬透性。更多还原

【Abstract】 Effect of Nb content on hardenability of 20 CrMnTi steel was investigated through Jominy tests. The test results show that for those specimens with different content of Nb,their hardness curves are approximately the same; their inflection points are all locateed in a distance range of 5-7 mm from the quenched end; the variation of microstructure with the distance from the quenched end is similar to each other.Therefore,the hardenability of 20 CrMnTi steel is not affected by Nb content. C contents and grain sizes are not affected by Nb,therefore the hardenability is not influenced by Nb; there is not enough Nb concentration in the solution to improve the hardenability of 20 CrMnTi steel;meanwhile,the precipitates containing Nb cannot induce the nucleation of ferrite and do not decrease the hardenability of 20 CrMnTi steel.更多还原