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研究了Ｎｉ－Ｂ４Ｃ复合镀层中，增强相Ｂ４Ｃ颗粒的热稳定性及镀层组成和性能的相应变化。金相显微结果表明，Ｂ４Ｃ颗粒在５００℃时开始分解，至８００℃分解完毕。Ｘ－ｒａｙ衍射、ＸＰＳ试验证实Ｂ４Ｃ颗粒分解后与Ｎｉ生成新相Ｎｉ３Ｂ，而且，由于Ｂ元素有着向镀层表面聚集的趋势，导致Ｎｉ３Ｂ首先在邻近表面的镀层中出现。Ｂ４Ｃ颗粒的分解，极大地降低镀层的硬度，但能有效地提高镀层的抗氧化能力。因此，Ｎｉ－Ｂ４Ｃ若作为耐磨材料，使用温度不宜大于５００℃，倘若利用它的抗氧化能力，即使在８００℃高温下，仍能耐受相当长的时间。
In the Ni-B4C composite coating, the thermal stability of the reinforcing phase B4C particles and the corresponding changes of the coating composition and properties were studied. Metallographic microscopic results show that, B4C particles began to decompose at 500 ℃, to 800 ℃ decomposition is completed. X-ray diffraction and XPS analysis confirmed that B4C particles formed a new phase of Ni3B with Ni after being decomposed. Moreover, Ni3B first appeared in the coating near the surface due to the tendency of B element to aggregate toward the coating surface. B4C particles decomposition, which greatly reduce the hardness of the coating, but can effectively improve the anti-oxidation coating. Therefore, Ni-B4C as a wear-resistant material, the use temperature should not exceed 500 ℃, if its antioxidant capacity, even at 800 ℃ high temperature, can withstand a long time.