Development of Supertough Ceramic or Cermet Thick Coatings Available in Various Surroundings

利用传统的电弧离子镀（AIP）源，对304型奥氏体不锈钢进行离子氮化，然后用Cr-Ni-N离子镀，其Ni含量在0 ~ 50%之间变化。在预氮化钢表面涂覆CrN陶瓷膜，即使在重载下也表现出良好的耐磨性。3 ~ 19μm CrN膜中，10μm CrN膜的磨损最小。含Ni的Cr-Ni-N薄膜由Cr^*N和Ni的混合相组成。Cr^*N是一种新发现的氮化铬，可能含有一些Ni，并已被确定为氟化碳结构。在预氮化钢表面涂覆镍含量为11%的Cr-Ni-N膜，其耐磨性在CrN膜和高镍含量Cr-Ni-N膜中表现最好。这种优异的耐磨性即使在薄膜厚度超过20μm时也能保持，这与CrN薄膜的趋势不同。此外，利用改进的AIP源在未处理或预氮化钢上沉积Cr-Ni-N薄膜，以减少沉积膜中的宏观颗粒数量。改性AIP源制备的膜比常规AIP源制备的膜具有更高的氮浓度。在低Ni含量的预氮化钢表面涂覆Cr-Ni-N膜，其摩擦系数最低，耐磨性最好。此外，发现高Ni含量的薄膜在不进行渗氮预处理的情况下表现出优异的耐磨性。在耐蚀性方面，低镍含量的CrN膜和Cr-Ni-N膜的耐蚀性最好。

Austenitic type 304 stainless steel was ion-nitrided and subsequently ion-plated with Cr-Ni-N whose Ni content was varied from 0 at% to 50 at%, utilizing the conventional AIP (arc ion plating) source. The ceramic film of CrN coated onto the pre-nitrided steel demonstrated good wear resistance even under a heavy load. Furthermore, a 10μm thick CrN film exhibited the least wear among the 3 to 19μm thick CrN films. The Cr-Ni-N films containing Ni were composed of mixed phases of Cr^*N and Ni.Cr^*N is a newly observed Cr nitride that may contain some Ni and has been identified as an f.c.t.structure. A Cr-Ni-N film with Ni content of 11 at% coated onto the pre-nitrided steel demonstrated the best wear resistance among the CrN film or Cr-Ni-N films with high Ni content. This superior wear resistance was maintained even at film thicknesses exceeding 20μm, unlike the tendency of CrN film.Furthermore the Cr-Ni-N thin films were deposited on the untreated or pre-nitrided steels utilizing a modified AIP source in order to reduce the number of macroparticles in these deposited films. The films deposited by the modified AIP source exhibited a higher nitrogen concentration than the films prepared by the conventional AIP source. The Cr-Ni-N films coated onto the pre-nitrided steels with a low Ni content demonstrated the lowest friction coefficient and the best wear resistance among these films. Furthermore, it was found that the films with a high Ni content exhibited the superior wear resistance without the pretreatment of nitriding.As for the corrosion resistance, the CrN film or Cr-Ni-N films with a low Ni content showed the best corrosion resistance among these films.