On this basis, the contrast test of die lifetime was done, the reasonable die material and face-hardened technology were determined.
在此基础上，进行了模具寿命对比试验，确定了合理的模具选材和表面强化工艺。
2
Japanese Vickers Hardened (VH) face-hardened, non-cemented armor (used only on YAMATO-Class battleships)…Steel had many tiny pieces of dirt and so forth.