| The current version does not support copying Cyrillic text to the Clipboard. You should activate the programpinholes is fewer and the size of droplets is smaller on the surface of (Ti,Ce)N and (Tii_zCrzCe)N coatings. According to the VDI 3198-1992 norm, Rockwell test adhesion class of all coatings is 1 at room temperature. Adhesion class of duplex TiN, (Ti,Ce)N and (Tio.7iCro.29Ce)N coatings is 1-2, while that of non-duplex TiN, (Ti,Ce)N and (Tio.7iCro.29Ce)N coatings is only 5-6 after 120 min heating and oxidation at 700°C. However, critical load of the duplex coatings is lower than that of the non-duplex coatings. The duplex coatings showed strain cracks within tracks which were followed by wide shell-like spallations outside the tracks due to occurrence of residual oxide on the surface of substrates after nitriding, sandblasting and cleaning, which is a challenge for the synthesis technology in a discontinuous mode. The thin Ti or TiCe adhesion layer can decrease considerably the number of shell-like spallations. Nitrided layer decreased effectively the crack density of coatings and increase the fracture toughness of coatings. The crack density of duplex coatings is lower greatly than that of non-duplex coatings at room temperature. It is found that the crack density of duplex (Ti,Ce)N coating after 120 min heating and oxidation at 700 °C is similar to that of non-duplex (Ti,Ce)N coating at room temperature, which means that the duplex (Ti,Ce)N coating still maintain enough fracture toughness after high temperature oxidation. The wear pattern observed in the non-duplex (Ti,Ce)N coating suggests the occurrence of a mixed mechanism involving grooving and rolling wear, while in the duplex (Ti,Ce)N coating suggests the occurrence of a mechanism basically involving rolling wear in the micro-load reciprocating wear test.Duplex TiN, CrN and (Ti,Cr)N coatings were synthesized in a continuous mode. Rockwell test adhesion class of duplex and non-duplex TiN, CrN and (Ti,Cr)N coatings is 1 at room temperature. Adhesion class of duplex CrN coating is still 1 after 120 min heating and oxidation at 700 °C. The critical load of duplex TiN, CrN and (Ti,Cr)N coatings is higher considerably than that of non-duplex TiN, CrN and (Ti,Cr)N coatings. Shell-like spallations outside the track also can not be observed, which shows good interface cohesion of duplex coatings and advantage of synthesis technology of duplex coatings in a continuous mode.Different Cerium content (Ti,Ce)N and duplex (Ti,Cr)N and (Ti,Cr,Ce)N coatingswere synthesized in a continuous mode using new 'suction' rare earth addition method. The Cerium content of the (Ti,Ce)N coating increases with the concentration of rare earth increasing, which means that it is feasible to control the Cerium content of the coatings by controlling the concentration of rare earth. Small amount of CeN phase with a (222) preferred orientation can be detected in the (Ti,Ce)N coatings. With the addition of Cerium, friction coeflBcient of the coating is smaller, which may be correlated with the number of droplets on the surface of the coating decreasing. The critical load of all (Ti,Ce)N coatings is very high and show perfect interface cohesion between substrate and coating. Shell-like spallations outside the track of the duplex (Ti,Cr)N and (Ti,Cr,Ce)N coatings also can not be observed. Adhesion class of all coatings is 1 at room temperature. Adhesion class of the duplex (Ti,Cr)N and (Ti,Cr,Ce)N coatings is still 1 after 120 min heating and oxidation at 700 °C. The crack density of the coatings with Cerium is lower significantly than that free of Cerium, i.e. the fracture toughness of the coatings with Cerium is higher. That is to say, Cerium can increase significantly the toughness of coating materials. According to the result, the crack density of the coating which Cerium content lower than 1% is the lowest. Cerium still shows strong ability to increase the toughness of the coatings after 120 min heating and oxidation at 700 °C.Lastly, duplex (Ti,Al,Ce)N and (Ti,Cr,Ce)N coatings on HSS screw dies was synthesized by arc ion plating in a discontinuous mode. Rockwell test adhesion class of the coatings is 1 at room temperature. Compared with the non-duplex (Ti,Al,Ce)N and (Ti,Cr,Ce)N coatings, durability of the duplex (Ti,Al,Ce)N and (Ti,Cr,Ce)N coatings increases 38% and 60%, respectively, which shows good mechanical property of duplex coatings.
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