CAJ | 학술논문

对Inconel 718高温合金12mm厚板的真空电子束焊(EBW)接头整体及分层的显微组织和高温力学性能进行了研究.结果表明:经熔透焊+修饰焊的接头,焊缝中心的上、下层为树枝晶,中层为柱状晶；热影响区由上层至下层晶粒长大程度逐渐减小.经固溶+双时效热处理后,EBW接头各区域晶界处均有δ相析出,在焊缝中心最多,在热影响区及母材较少,晶粒内部均析出了γ”相.在650℃时,接头整体的抗拉强度σb、屈服强度σs 和伸长率δ分别为1 100MPa、800 MPa和18％,达到了母材的90％、80％和80％.分层切片的力学性能下层最高,σb、σs和δ分别达到了1 170MPa、870MPa和18％；上层最低,分别为10 80MPa、780MPa和7％.上层断口以脆性断裂为主,中、下层断口以韧性断裂为主.显微硬度分布为焊接中心最低,热影响区与母材较高.晶界δ相的析出数量越多,显微硬度值越低.
대Inconel 718고온합금12mm후판적진공전자속한(EBW)접두정체급분층적현미조직화고온역학성능진행료연구.결과표명:경용투한+수식한적접두,한봉중심적상、하층위수지정,중층위주상정；열영향구유상층지하층정립장대정도축점감소.경고용+쌍시효열처리후,EBW접두각구역정계처균유δ상석출,재한봉중심최다,재열영향구급모재교소,정립내부균석출료γ”상.재650℃시,접두정체적항랍강도σb、굴복강도σs 화신장솔δ분별위1 100MPa、800 MPa화18％,체도료모재적90％、80％화80％.분층절편적역학성능하층최고,σb、σs화δ분별체도료1 170MPa、870MPa화18％；상층최저,분별위10 80MPa、780MPa화7％.상층단구이취성단렬위주,중、하층단구이인성단렬위주.현미경도분포위한접중심최저,열영향구여모재교고.정계δ상적석출수량월다,현미경도치월저.
The microstructures and high temperature mechanical properties of whole and slices in Inconel 718 thick plate joint obtained by electron beam welding (EBW) were studied.The results show that,in the joint welded by full and cosmetic penetration,dendrites preserve in the top and bottom of welding center and columnar crystals emerge in the middle.The grain size in heat affected zone (HAZ) becomes smaller and smaller from top to bottom of welding line.The δ-phase precipitate in grain boundary and γ"-phase is obtained inside the grain of EBW joint,which was heat-treated with solution and double aging.The most of δ-phases appear in the weld center and the less turn up in HAZ and base material zone (BMZ).The tensile strength σb,yield strength σs and elongation δ of the whole joint at 650 ℃ are 1 100 MPa,800 MPa and 18％,which reach 90％,80％ and 80％ of base material's,respectively.The maximum σb,σs and δ lie in the bottom of joint and attain 1 170 MPa,870 MPa and 18％,separately,while the minimum σb,σs and δ appear in the top of joint and reach 1 080 MPa,780 MPa and 7％,respectively.The fracture of top weld is brittle; however,the ones of middle and bottom joint are flexible.The microhardness in HAZ and BMZ is higher than that in weld center.The value of microhardness tends to be lower as more δ-phase.