热处理温度对超高强度钢组织性能的影响

为了改善超高强度钢的塑韧性，实验分析了奥氏体化温度分别为840℃、880℃、920℃与等温温度分别为275℃、325℃、375℃对中碳超高强度钢组织性能的影响．结果表明，随着奥氏体化加热温度的升高，贝氏体/马氏体复相组织趋向粗大，钢的强度上升，而塑韧性下降；随着等温温度的升高，钢的抗拉强度呈平缓下降趋势，而钢的塑韧性在275～325℃等温温度范围内呈上升趋势，在325～375℃等温温度范围内呈下降趋势．在试验等温处理温度范围内，奥氏体化温度880℃×30min保温＋等温温度325℃×2min保温油冷，可获得强韧性配合良好的贝氏体/马氏体复相组织，钢的残余奥氏体的含碳量≥76．％，钢的抗拉强度Rm≥2065M Pa ，断面收缩率ψ≥255．％．

Heat treatment temperature on the properties of ultra high strength steel groupShangQiu Polytechnic

In order to improve ultrahigh strength steel plastic toughness ,the experiment analyzed the austenitizing temperature 840 ℃ ,880℃ and 880 ℃ respectively and isothermal temperature 275 ℃ ,325 ℃ and 325 ℃ respectively affect the performance of carbon in the ultra -high strength steel group .The results showed that with the increase of austenitizing temperature ,the bainite/martensite phase organization tends to bulky ,rise ,strength of steel and plastic toughness drops ;With the increase of isothermal temperature ,the tensile strength of steel is gently downward trend ,while steel plastic toughness in 275 -325 ℃ isothermal temperature range is on the rise ,in 325 -375 ℃ isothermal temperature range is on the decline .In test of isothermal treatment temperature range ,the austenitizing temperature is 880 ℃ for 30 min insulation ＋ 325 ℃ isothermal temperature x 2 min insulation oil cold strong toughness can be obtained with good bainite/martensite phase organization ,the residual austenite steel the carbon content of 7 6.% or more ,the tensile strength of steel Rm 2065 mpa ,or reduction of area bits of 25 5.% or higher.