硬质合金注射成形注射参数的优化

Optimization of Tungsten Cemented Carbide Injection Molding Process Parameters

采用正交实验设计的方法 ,系统的研究了注射压力、注射温度、注射速度、模具温度及其交互作用对注射成形生坯质量的影响 ,通过直观分析和方差分析 ,评价了各参数影响生坯质量的显著程度 ,优化了注射成形参数。结果表明 :注射温度、注射压力及注射温度与模具温度的交互作用对生坯强度影响显著 ,注射温度和注射压力对生坯密度影响显著 ;注射压力增加 ,生坯密度和抗弯强度都增高 ;注射温度增高 ,生坯密度降低 ,注射温度在 165℃～ 170℃之间时 ,成形坯抗弯强度变化不大 ,175℃时明显下降 ;模具温度和注射速度分别为 3 0℃和 60 %时 ,生坯密度、抗弯强度达到最高值 ;尺寸为 6mm× 6mm× 42mm矩形生坯的最佳注射参数为 :注射压力 14 4MPa ;注射温度165℃ ;注射速度 60 % ;模具温度 3 0℃。

The influence of key injection molding process parameters including injection pressure, barrel and die temperature, and injection speed on the density and strength of the as-molded specimens has been studied using orthogonal arrays experimental design and statistical analysis method. It is found that injection pressure, barrel temperature, and its interaction with die temperature have distinguished influence on strength, while injection pressure and barrel temperatures have remarkable effect on density. The density and strength tend to increase as injection pressure increases. However, the density decreases as injection temperature increases, the strength keeps almost constant when the barrel temperature is between 165℃～170℃ and decreases sharply when the barrel temperature reaches to 175℃. The density and strength achieve the best values when die temperature and injection speed are 30℃ and 60% respectively. The optimized injection parameters for rectangular specimens with a dimension of 6mm×6mm×42mm are as following: injection pressure 144MPa, injection temperature 165℃, injection speed 60% and die temperature 30℃.