| Self-developed high aluminum bronze (Cu-14Al-X) alloy powder materials wereprepared and then coated them onto substrate recently. Our research groups havestudied deeply the preparation, mechanical properties, friction and wear, corrosion andwear performances of the coatings, which showed excellent wear resistance and handlethe tough. In order to improve the performances of Cu-14Al-X and expand theapplication of rare earth Ce, The powders of Cu-14Al-X alloy without Ce and with0.6%Ce were prepared by water atomization technology. The powders were sprayedon45carbon steel substrate using supersonic plasma spraying. And the effects of rareearth Ce on the microstructure and wear resistance were investigated. Meanwhile, thefriction properties of coatings and Cu-14Al-X alloy were compared under the samecondition of friction.The effect of rare earth Ce on the microstructure, compositions and phasestructure of Cu-14Al-X coatings were investigated by Light Microscopy, X-raydiffraction analysis, SEM and EPMA. The results showed that the two supersonicplasma sprayed coatings were the composition of white, black, gray phase, and therewere most flat and few spherical particles on the organization of spray coating. Thespray coatings were relatively uniform, dense, and lamellar, and the spotty black phasedispersed in the gray phase. After adding rare earth Ce, gray lamellar strucures arereduced, gray flat-shaped particles are refined and its dispersivity is increased. Andblack phase and white phase increased significantly with the distribution of moreuniform punctate in the gray phase. The phases of the two spray coatings and powderare mainlythe same because of the composed of the same phase of α+β’+γ2+K.Howere, the diffraction peaks of supersonic plasma spray layer become broadcompared with the powder, and the K-phase diffraction peak was significantlyenhanced adding into Ce.The performances of the supersonic plasma spray layer with and without Ce wereinvestigated by doing friction experiment with RFT-III friction machine under boundary lubrication. The results suggested that the abrasion format of the coatingswithout Ce was mainly as a mild adhesive wear and minor abrasive wear at low load.The adhesive wear became more and more serious with the increasing of the load. aThe phenomenon of stratified wear appeared when the load is increased to392N, andthen it was transformed into severe abrasive wear when the load is increased to490N.The main abrasion format of the coatings with0.6%Ce is mild abrasive wear, and itbecome moderately abrasive wear eventually at high loads (490N). Some areas offriction hardening occurs, but the scratch is more detailed and uniform.The friction properties of coatings and Cu-14Al-X alloy were compared under thesame condition of friction. The results show that the abrasion mechanism of theCu-14Al-X alloy is similar to the supersonic plasma sprayed coatings containing Ce,ismostly abrasive wear. The wear amounts of the supersonic plasma sprayed coatingswithout Ce and the Cu-14Al-X alloy are the same roughly at low loads under boundarytribological condition. The hard K phase, β and γ2phase in spray coatings with Ce arefiner and more uniform distribution. Spray coatings with Ce showed superior wear andfriction properties in the friction process. At the same time，the coefficient of frictionand wear amount is much lower than the Cu-14Al-X alloy. |
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