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Abrasive Wear (abrasive + wear)
Selected AbstractsAbrasive Wear of DLC/PVD Multilayer Coatings: AFM StudiesLUBRICATION SCIENCE, Issue 3 2004C. Martini Abstract The tribological behaviour of multilayered coatings deposited on plain carbon steel was investigated by microscale abrasion tests (MSATs). The multilayered coatings consisted of an outer diamond-like carbon (DLC) layer, a physical vapour deposition (PVD) nitride-based interlayer, and an inner electroless Ni-P layer. PVD TiN- and Ti(C,N)-coated samples with and without the DLC outer layer were studied in order to evaluate the influence of each layer on the tribological behaviour of the multilayer-coated system. The MSATs were carried out using a device based on ball-cratering geometry: a hard steel sphere was rotated against the coated specimen in the presence of an aqueous suspension of SiC particles. The wear coefficients of the multilayers were calculated from the diameter of the wear craters. The morphology of the wear scars produced by the MSATs was studied by atomic force microscopy (AFM). The wear damage was described by measuring the r.m.s. roughness (Sq) on the sides of the wear craters. Roughness values were related to the wear coefficients (kc) for the different multilayers on the basis of mathematical elaboration typical of the ,design of experiment' (DOE) statistical technique. The presence of the DLC outer layer reduced the roughness of the crater sides and significantly increased the wear resistance of the multilayer only in the case of the PVD TiN sublayer. [source] Influence of Surface Modification on the Cutting Performance of Reaction-Sintered Al2O3,TiOC CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2008Anup K. Bhattacharya Al2O3,TiC mixed ceramics are popular for dry cutting of hardened steel. In this work, the cutting performance of surface-modified mixed ceramic cutting tools has been studied. A 1-,m-thick modified surface has been obtained by CO2 posttreatment of the Al2O3,TiOC mixed ceramics. The cutting performance of the modified tools has been found to be much better than the precursor-mixed ceramics. The density of the modified layer also has an influence on the cutting performance. Modified ceramics with a dense surface layer show considerably improved wear resistance compared with that of ceramics with a porous layer. While plastic deformation of the TiC layer in the flank surface, followed by abrasive wear of the exposed substrate is responsible for flank wear, crater wear is caused mainly by diffusion reaction as well as by abrasion. In our system, it is mainly the flank wear that controls the cutting performance of the inserts. [source] Tribological Behavior of SiC-Reinforced Ti3SiC2 -Based Composites under Dry Condition and under Lubricated Condition with Water and EthanolJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2006Yuko Hibi To evaluate the lubrication compatibility of SiC-reinforced Ti3SiC2 -based composites, i.e., a Ti3SiC2/SiC composite, with water and alcohol, sliding experiments were conducted under dry condition and lubricated with water and C2H5OH. The friction and wear of the Ti3SiC2/SiC composite decreased in the order of dry condition, in water, and in C2H5OH. The worn surfaces indicated that oxide masses, which caused oxidation wear and abrasive wear, were formed by tribo-oxidation on the sliding surface under the dry condition and in water, while tribo-oxidation scarcely occurred in C2H5OH. [source] Microabrasion of Coatings Investigated by the Inclined Impact Test at Various Loads under Dry and Lubricated ConditionsPLASMA PROCESSES AND POLYMERS, Issue S1 2007Konstantinos-Dionysios Bouzakis Abstract The impact test has clearly emerged as an important technology for the prediction of cohesive, adhesive, and fatigue failure of coatings, further enabling the establishment of Smith and Woehler diagrams of PVD films. In the present paper, the abrasive wear of a well-adherent (Ti46Al54)N coating was investigated by the inclined impact test, at impact loads higher, equal to or lower than the fatigue critical impact load of the applied film. These investigations were conducted for few thousands up to several millions of impacts both under dry and lubricated conditions. The obtained results suggest that the inclined impact test is a very efficient method for detecting coating resistance against impact microabrasion, with or without lubrication and according to the test conditions for the synchronous contribution of fatigue phenomena to the film wear. [source] Influence of fiber orientation on high stress wear behavior of sisal fiber-reinforced epoxy compositesPOLYMER COMPOSITES, Issue 4 2007Navin Chand Sisal fiber-reinforced epoxy composites having three different fiber orientations, namely LL, LT, TT mentioned in the text were prepared and tested for their high stress abrasive wear behavior. Effect of fiber orientation, sliding distance, and load on abrasive wear of sisal,epoxy composites have been determined. Wear data of composites have been compared with the pure epoxy. Incorporation of fibers decreases the wear rate of epoxy resin, which varies with the fiber orientation. Wear rate in case of TT composite is found minimum as compared to other two composites. Wear rate follows the following trend, WTT < WLT < WLL. Owing to minimum exposed area of fiber to the sliding asperities, lowest wear rate occurs in the case of TT composite. Increase of load and sliding distance increases the wear volume in all the composites, because of the progressive loss of material. Wear mechanism has been discussed by using SEM micrographs of the worn surfaces. POLYM. COMPOS., 28:437,441, 2007. © 2007 Society of Plastics Engineers. [source] Development of UHMWPE modified PP/PET blends and their mechanical and abrasive wear behaviorPOLYMER COMPOSITES, Issue 2 2007Navin Chand In this study, polypropylene and polyethylene terephthalate blend were modified by incorporating different percentages of ultrahigh molecular weight polyethylene (UHMWPE) ranging from 1 to 5 phr. Modified blends were prepared by melt mixing the PP/PET blend and UHMWPE. Ultimate tensile strength of UHMWPE filled blend was determined at 10, 20, 50, and 100 mm/min cross head speeds of testing. It was found that increase of cross head speed from 10 to 100 mm/min increases the tensile strength of PP/PET/UHMWPE blends. Maximum ultimate tensile strength is exhibited by the blend containing 2 phr UHMWPE. Breaking strain of the UHMWPE modified and unmodified PP/PET blend increased with the increase of cross head speed due to the highly entangled chain structure of UHMWPE. Shore A hardness of the filled blends also increased from 341 to 356, which is highest for 2 phr UHMWPE. High stress abrasive wear of UHMWPE modified blend was determined by using Suga abrasion tester, model NUS-1 Japan. Wear rate of the PP/PET(90/10) blends having 1, 2, and 5 phr of UHMWPE was determined at different loads such as 1, 3, 5, and 7 N and sliding distances from 6.4 m to 25.6 m. Wear rate values show that UHMWPE has prominent effect on abrasive wear of PP/PET blends. Addition of 2 and 5 phr UHMWPE improved the wear resistance of PP/PET blends at different loads, which has been explained on the basis of improved bonding as compared with pure PP/PET blend and increased hardness. Maximum abrasive wear rate reduction was achieved by adding 2 phr UHMWPE in PP/PET(90/10) blend. POLYM. COMPOS. 28:267,272, 2007. © 2007 Society of Plastics Engineers [source] | ||||||||||