学科分类
/ 1
1 个结果
  • 简介:ThesecondaryhardeningreactionisaccompaniedwithprecipitationoffinecarbidesinhighCoNiultrahighstrengthsteel.Thecrystalstructureoftheprecipitatingcarbidesisunambiguouslydeterminedbymicrobeamdiffractionintransmissionelectronmicroscopy.Itisidentifiedthattheneedle-shapedcarbidesareM2Cwithahexagonalstructure.TheconcentrationofsubstitutionalalloyingelementsinthecarbidesquantifiedbyenergydispersiveX-rayspectroscopy(EDS)alsosupportstheresultabove.ThespatialstructureofM2CisidenticalwithL'3type.Metalatomsareinaclosepackedhexagonalstructure,thecarbonatomspartlydistributewithrandomintheoctahedralintersticesandthefillingprobabilityislessthan1/2.Particularattentionwaspaidtotherelationshipofneedle-shapedcarbides/ferritematrixatsecondaryhardeningpeaktemperedat482℃for5h.Observationbyhighresolutiontransmissionelectronmicroscopy(HRTEM)confirmsthatcarbideswithblack-whitecontrastarefullycoherentwithferriteandhaveindividualcrystalstructure,andthecoarsenedcarbideswithmoirefringearepartiallycoherentwithmatrix.TheorientationrelationshipbetweenM2CandferritematrixisdirectlyobservedandidentifiedwiththewellestablishedP-Srelationship[001]α//[111]c.

  • 标签: 钴镍 超高强度钢 X射线光谱 碳化物沉淀 HRTEM 二次硬化合金钢