模套预应力对合金模坯强度的影响

合金模坯镶套过程中常见的几种缺陷，是影响合金模坯在使用过程中使用寿命的主要原因之一，解决这个问题的主要手段是提高模套与模坯之间的接触面，使模套的预加应力很有效地传递到模坯上，从而达到或抵消模坯所承受的工作应力。通过实践证明，模套与模坯之间有良好的接触面，模坯的抗张力和抗冲周力增强，从而减少和消除硬质合金模坯在使用过程中的破碎率，提高使用寿命。

THE INFLUENCE OF THE PRESTRESS OF CASES ON THE DIE STRENGTH OF CEMENTED CARBIDE

Several kinds of common shortcomings for casing of die are the main reason which shorten the service life of alloy mould. The essential method to solve this problem is increasing the contact surface between the case and the die,thus the prestress of the case is transmitted to the die effectively,the work stress on the die is reached or off-set. The practise shows that fine contact surface between the case and the die,increased tension stress and shock resistance of die can reduce or eliminate the crushing ratio by using cemented carbide die and increase service life.