Cu/Sb/Sn/Mo/W对新国标09CrCuSb钢组织及力学性能的影响

采用金相显微镜、扫描电镜、电子探针、拉伸力学性能测试、夏比冲击测试，研究了新国标NB/T47019-2021的09CrCuSb钢合金元素Cu、Sb、Sn、Mo和W对其微观组织和力学性能的影响。研究表明，新标准中增加的合金元素将促进钢中δ-铁素体的析出，同时也会增加材料强度但会降低其塑性；δ-铁素体将显著降低材料冲击力学性能其中，R_p0.2=365.64 MPa,夏比冲击功KV₂为243 J(室温)和192 J(-40℃)],使得冲击断口由塑性断口向脆性断口特征转变，特别是对-40℃的冲击功降低作用尤为显著。在新国标成分框架下，须通过合理的热加工工艺调整，降低钢中δ-铁素体的析出，从而提高材料力学性能。

Effect of Cu/Sb/Sn/Mo/W on Structure and Mechanical Properties of New National Standard 09CrCuSb Steel

In this paper,the effects of alloy elements Cu,Sb,Sn,Mo and W of new national standard 09CrCuSb on their microstructure and mechanical properties are studied by means of metallographic microscope,scanning electron microscope, EPMA,tensile mechanical property test and Charpy impact test. The results show that the addition of alloying elements will promote the precipitation of δ-ferrite to increase the strength of the material but reduce its plasticity;δ-ferrite will significantly reduce the impact mechanical properties of the material,making the impact fracture change from plastic fracture to brittle fracture,especially for the impact energy at -40 ℃Among them,R_p0.2=365.64 MPa,Charpy impact energies K_V2 243 J(ambient)and 192 J(-40℃)].Under the framework of the new national standard composition,it is necessary to adjust the reasonable hot working process to reduce the precipitation of δ-ferrite and improve the mechanical properties of the material.