文章编号：1671-7872(2023)02-0133-06Cr5支撑辊材料过冷奥氏体连续冷却组织转变特征赵士光1，张响响2，王成1，高安阳1，斯庭智2(1.安徽马钢重型机械制造有限公司技术中心,安徽马鞍山243000；2.安徽工业大学材料科学与工程学院,安徽马鞍山243032)摘要：采用热模拟试验机测试Cr5系支撑辊材料的热膨胀曲线，绘制支撑辊下限成分Cr5L和上限成分Cr5U试样的过冷奥氏体连续冷却组织转变(CCT)曲线，研究材料的组织转变特征和硬度变化规律。结果表明：与Cr5L试样相比，Cr5U试样具有更低的马氏体形成起始温度(Ms)和结束温度(Mf)，分别为279，153℃；上限成分提高了钢的淬透性，马氏体(M)转变临界冷却速度由Cr5L试样的1.00℃/s下降到0.50℃/s。Cr5L和Cr5U试样过冷奥氏体(A’)连续冷却均发生珠光体(P)、贝氏体(B)和M转变，且P和B转变“C”曲线发生分离，具有双“C”曲线特征；Cr5L和Cr5U试样B转变分别形成B下(B1)和B粒(B2)，且Cr5U试样M组织中含质量分数约6%的软韧相残余奥氏体(Ar)，故以大于B临界冷却速度冷却的Cr5U试样维度硬度值小于Cr5L试样。关键词：Cr5支撑辊；连续冷却转变；显微组织；相结构；硬度中图分类号：TG142.1+2文献标志码：Adoi：10.12415/j.issn.1671−7872.22316MicrostructureTransformationCharacteristicsofSupercooledAusteniteofCr5Back-upRollsDuringContinuousCoolingZHAOShiguang1,ZHANGXiangxiang2,WANGCheng1,GAOAnyang1,SITingzhi2(1.TechnologyCenter,MasteelHeavyMachineryManufacturingCompanyofAnhui,Maanshan243000,China;2.SchoolofMaterialsScience&Engineering,AnhuiUniversityofTechnology,Maanshan243032,China)Abstract：ThermalmechanicalsimulatorwasusedtotesttheexpansioncurvesofCr5seriesback-uprolls,andthecontinuouscoolingtransformation(CCT)curvesofsupercooledausteniteweresketchedfortheCr5LandCr5Usampleswithlowerandupperlimitcompositions,respectively.Furthermore,thecharacteristicsofmicrostructuraltransformationandhardnessevolutionswerealsoinvestigated.TheresultsshowthatcomparedwithCr5Lsample,Cr5Usamplehasthelowerinitialtemperature(Ms)andendtemperature(Mf)ofmartensiteformation,whichare279and153℃respectively.Theupperlimitcompositioncanimprovehardenabilityofsteel,andthecriticalcoolingrateofmartensite(M)transformationforCr5Lsampledecreasesfrom1.00℃/sto0.50℃...
