大气层流等离子体表面淬火对QT450微观组织及硬度的影响.pdfVIP

HotWorkingTechnology2020,Vol.49,No.4

大气层流等离子体表面淬火对QT450

微观组织及硬度的影响

帅帆,范洪远,王均,苏武丽

(四川大学制造科学与工程学院,四川成都610065)

摘要：利用大气层流等离子体对QT450铸铁进行表面淬火，研究了不同扫面速率下大气层流等离子体淬火对铸

铁表面去石墨化及石墨形貌的影响。结果表明：随着等离子体扫描速率的增加，淬透深度逐渐下降。金相和SEM图片显

示：在等离子体淬火后基体组织无明显变化；淬火层与基体的过渡区域中石墨边缘形貌模糊化，并且有共晶渗碳

QT450

体和针状马氏体生成；淬火区域的石墨相完全消失，并出现了隐针马氏体、残余奥氏体及渗碳体等新相，材料表层硬度

显著提高。

关键词：铸铁；表面淬火；等离子束；淬硬层深

DOI:10.14158/j.cnki.1001-3814.

中图分类号：；文献标识码：文章编号：

TG163TG156.33A1001-3814(2020)4-0136-04

EffectsofLaminarPlasmaSurfaceQuenchingonMicrostructure

andHardnessofQT450

SHUAIFan,FANHongyuan,WANGJun,SUWuli

(SchoolofManufacturingScienceandEngineering,SichuanUniversity,Chengdu610065,China)

：

AbstractQT450castironwasquenchedbyatmosphericplasma,andtheeffectsofplasmaquenchingonthesurface

degraphitizationandgraphitemorphologyofcastironatdifferentsweeprateswasstudied.Theresultsshowthat,withthe

increaseofplasmascanningrate,thequenchingdepthdecreasesgradually.MetallographyandSEMimagesshowthatQT450

matrixstructurehasnoobviouschangeafterplasmaquenching.Themorphologyofgraphiteedgeinthetransitionzone

betweenquenchinglayerandmatrixisblurred,andeutecticcementiteandacicularmartensiteareformed.Thegraphitephase

inquenchingregiondisappearscompletely,andso