The combination of high temperature indentation and wear test provides a useful way to investigate wear of CrN coating and wear transition mechanisms. In this paper, the high temperature hardness of CrN coatings and load bearing capacity, L_b, of CrN coated M50 disks were determined from spherical indentation at temperatures up to 500 °C. Wear tests with different normal loads were carried out at the same temperatures as the indentation tests. The results show that wear mechanism of CrN coating changes with external load, P, and temperature, T. Under a tested condition of P < L_b and T < 315 °C, abrasive is the dominant wear mechanism for CrN coating. Under a tested condition of P < L_b and T ≥ 315 °C, wear of CrN coating transitions into mild oxidation wear due to the lubricating effect of chromium oxide film. Under a tested condition of P > L_b and T < 315 °C, wear of CrN coating was controlled by coating fracture. Under a tested condition of P > L_b and T ≥ 315 °C, wear of CrN coating transitions into the severe wear mode, due to the tensile fracture of oxidation films, thereby leading to adhesion between CrN coating and tribo-counterpart. The presented method can be helpful in predicting permissible load and working temperature in tribological applications of CrN coating.

Our aim was to demonstrate how competition among nonprofit organizations (NPOs) influences people's charitable behaviors, such as donating and volunteering. We used structural equation modeling to analyze 205 responses from: (a) randomly selected individuals on the donor lists of 3 leading NPOs in China, and (b) students at 3 large universities in China. The results reveal that as competition amongst NPOs increased, the individuals' identification with NPOs became greater. Further, as the respondents' NPO identification increased, their charitable behaviors relative to the organization also increased; thus, identification played a mediating role between competition and donating and/or volunteering. These findings suggest that managers of NPOs can use competition to help potential supporters better identify with those organizations, increasing the likelihood of gaining support by more effectively distinguishing their organization from other NPOs. Given that we found donations were a direct result of identification, advertising efforts should be focused on creating a distinctive NPO identity with which members of the public can relate.

In this paper, interfacial stress analysis for a brittle coating/ductile substrate system, which is involved in a sliding contact with a rigid ball, is presented. By combining interface mechanics theory and the image point method, stress and displacement responses within a coated material for normal load, tangential load, and thermal load are obtained; further, the Green’s functions are established. The effects of coating thickness, friction coefficient, and a coating’s thermoelastic properties on the interfacial shear stress, τ_xz, and transverse stress, σ_xx, distributions are discussed in detail. A phenomenon, where interfacial shear stress tends to be relieved by frictional heating, is found in the case of a coating material’s thermal expansion coefficient being less than a substrate material’s thermal expansion coefficient. Additionally, numerical results show that distribution of interfacial stress can be altered and, therefore, interfacial damage can be modified by adjusting a coating’s structural parameters and thermoelastic properties.