摘要
对W-40%Cu(质量分数)粉末烧结材料在热加工数值模拟过程中需要确定的坯料与模具间的界面摩擦因子,以及与空气、模具间的换热系数进行了测定。摩擦因子直接通过圆环镦粗实验来确定。采用DEFORM软件对坯料传热过程中温度的变化进行了模拟,并将模拟得到的温度变化曲线与实际传热实验中获得的温度变化曲线相比较,确定了坯料在不同条件下的换热系数。结果显示,坯料在无润滑时与模具间摩擦因子为0.36,在石墨油润滑时为0.11;与空气自然对流换热系数取0.021N/(s.mm.℃),与模具无润滑剂接触时换热系数取0.11N/(s.mm.℃);加石墨油润滑且接触应力很小时取0.62N/(s.mm.℃),随着接触面应力从0.06MPa增大到90MPa,换热系数逐渐从3.4N/(s.mm.℃)增加到11N/(s.mm.℃)。
In this paper, the friction-factor between workpiece of W-40wt% Cu powder sintered composite and die, and the heat transfer coefficient between workpiece and air or die during hot processing have been measured. The friction-factor is determined by the ring upset test. The variation of workpiece temperature in the heat transfer test is simulated by DEFORM, which is used to compare with the experimental data to determine the heat transfer coefficient under different conditions. The results show that, the friction-factor between the workpiece and die is 0. 36 in dry friction test and 0. 11 with oil and graphite lubricated; the convection coefficient is 0.021N/（s·mm·℃） contacted with air, 0. 11N/（s·mm·℃） without lubrication between workpiece and die, 0. 62N/（s·mm·℃） with oil and graphite lubricated. With the increase of the contact stress from 0. 06MPa to 90MPa, the heat transfer coefficient is increased from 3.4N/（s·mm·℃） to 11N/（s·mm·℃） gradually.
出处
《粉末冶金技术》
CAS
CSCD
北大核心
2009年第3期178-181,211,共5页
Powder Metallurgy Technology
基金
国家自然科学基金资助项目(50575050)
关键词
W-40%Cu粉末烧结材料
摩擦因子
换热系数
数值模拟
W-4Owt% Cu powder sintercd composite
Friction-factor
Heat transfer coefficient
Numerical simulation
