Zr--4合金应力松弛过程中的热激活变形与动态应变时效

1、pp;(3);(4),.,.,t=0t=slnt+c(t0)(1),.,.(473873K)15,t;0;s.(1)tcZr4,.;.,.,.,Zr4.12mmZr4,(,%):Sn1.45,Fe0.21,Cr0.11,O0.12,Zr.,MTS809A/T(25kN).,900s;900s.1.873K,MTS653,1K.,500400aPM300,ssertS200100Strain1Zr4Zr4alloy(relaxation900s,temperaturerange:RT873K),.,.,1dtp=e=Edt(2),p,e;E.(1)dtsdt=t(3)1

2、dp=Etsdt=Et(4)(4).30.08),.,100600s.,623K(3ab)573K(3c)10080aP60M402002004006008001000t, sFig.2Relationshipbetweenstressreduction(0t)andrelaxationtimett, sFig.3Variationsofplasticdeformationratepwithrelax-ationtimetatdierenttemperaturesandstrainsof0.02(a),0.05(b)and0.08(c).(0900)/0,4.900(900s).,),.,62

3、3K.,.623K,.;,.,.,.,.,.vG9v=v0exp(GkT)(5),kBoltzmann;T;v0,.1017645p=mbv/M(6)m,;bBurgers;MTaylor,.,b=3.231010m11,M=412.(5)(6)p=0exp(GkT)(7),0,.(G0),G0=G+blR/M(8),;lR;blR(V),13,V=blR=G/MT(9)(7),V= G lnp/MT=kT/M T(10),.,.,.,dt=d(11)(2),(8)(7),(11)d (GV/M)dt=E0exp0kT(12),(1).(4),dlnp1dt=t(13)(3),(11)(13)

4、dlnp1d=s(14)(14)(10),V=kT lnp/M T=MkTs(15)(15).5,Zr4.Burg-ers(b3).623573K,.,623K.,.,.,(3).Zr4(4).5:,;(373K),.,.,.,Zr4.,.,.,.14,.b,emulovnoitavitcA300400500600700800900Temperature, K5dierentstrains2:Zr41774(1)Zr4,.Zr4,.(2):,;,Zr4623K;Zr4.1LeeMH,KimJH,ChoiBK,JeongYH.JAlloysCompd,2007;428:992AhnJS,NamS

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