渗碳的计算机模拟及程序

20钢在碳含量为1.2%的渗碳气氛中渗碳情况程序：co=0.2;cp=1.2;d=0.162*exp((-137800)/(8.314*1203));x=0.0437*exp((-79953)/(8.314*1203));t=3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c)holdon;t=4*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c)holdon;t=8*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c)holdon;t=20*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c)holdon;co=0.2;cp=1.2;d=0.162*exp((-137800)/(8.314*1203));x=0.0473*2*exp((-79953)/(8.314*1203));t=3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c,'-.')holdon;t=4*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c,'-.')holdon;t=8*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c,'-.')holdon;t=20*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c,'-.')holdon;其中虚线为界面传递系数增大一倍时的渗碳情况。从左至右依次是1、4、8、20小时的渗碳曲线。碳浓度随渗碳层厚度的变化x/cmc/%20钢在碳含量为1.2%的渗碳气氛中渗碳情况程序：co=0.2;cp=1.2;d=0.162*exp((-137800)/(8.314*1203));x=0.0437*exp((-79953)/(8.314*1203));t=3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c)holdon;t=4*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c)holdon;t=8*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c)holdon;t=20*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c)holdon;co=0.2;cp=1.2;d=2*0.162*exp((-137800)/(8.314*1203));x=0.0473*2*exp((-79953)/(8.314*1203));t=3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c,'-.')holdon;t=4*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c,'-.')holdon;t=8*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c,'-.')holdon;t=20*3600;a=0:0.01:0.5;c=co+(cp-co).*(erfc(a/(2.*(d.*t)^0.5))-exp((x.*a+x^2.*t)/d).*erfc(a/(2.*(d.*t)^0.5)+x.*(t/d)^0.5));plot(a,c,'-.')holdon;其中虚线为扩散系数D增大一倍时的渗碳情况。从左至右依次是1、4、8、20小时的渗碳曲线。碳浓度随渗碳层厚度的变化x/cmc/%20钢在碳含量为1.2%的渗碳气氛中以离子渗碳方式渗碳时的渗碳情况程序：co=0.2;cp=1.2;d=0.162*exp((-137800)/(8.314*1203));a=0:0.01:0.5;t=1*3600;c=co+(cp-co).*erfc(a/(2.*(d.*t)^0.5));plot(a,c);holdon;t=4*3600;c=co+(cp-co).*erfc(a/(2.*(d.*t)^0.5));plot(a,c);holdon;t=8*3600;c=co+(cp-co).*erfc(a/(2.*(d.*t)^0.5));plot(a,c);holdon;t=20*3600;c=co+(cp-co).*erfc(a/(2.*(d.*t)^0.5));plot(a,c);holdon;图中从左至右依次为渗碳1、4、8、20小时的渗碳曲线。碳浓度随渗碳层厚度的变化x/cmc/%碳浓度为0.38%渗碳层厚度随时间的变化情况程序：d=0.162*exp((-137800)/(8.314*1203));t=0:0.01:20;a=1.9.*(d.*t.*3600).^0.5;plot(t,a);holdon;渗碳层厚度随时间的变化情况t/hx/cm渗碳20小时碳浓度为0.38%的渗碳层厚度随温度的变化情况程序:t=1203:1:1323;d=0.162.*exp((-137800)./(8.314.*t));a=1.9.*(d.*72000).^0.5;plot(t,a);holdon;渗碳20小时碳浓度为0.38%的渗碳层厚度随温度的变化情况T/kx/cm