Zinc-oxide (ZnO), a solid lubricant coating, can increase the wear resistance of steels by working as a self-lubricant. In this study, ZnO film is synthesized using the cathodic cage plasma deposition (CCPD) technique, using galvanized steel cathodic cage (steel cage with zinc coating). The effect of gas composition (H₂ is added in Ar-O₂) is investigated to optimize the film properties. The surface hardness is increased more than twice in each processing condition. The deposited film shows ZnO phases for samples treated with low hydrogen contents and a combination of ZnO and magnetite phase (Fe₃O₄) with higher hydrogen contents. The thickness of film reduced from 1.28 μm to 0.5 μm by increasing the hydrogen composition. The wear resistance is expressively increased by film deposition, and the abrasive wear mechanism is changed to an adhesive wear mechanism. A significant decrease in wear rate is observed, specifically by increasing the hydrogen contents. The friction coefficient as a function of sliding distance is smoother and lower than the base material in each condition. This study suggests that the CCPD technique can effectively deposit the solid lubricant coating of ZnO, and it can be used to enhance the tribological properties of steel samples. Moreover, this technique is convenient due to its better deposition efficiency, eco-friendly (no chemicals are involved), simple and relatively low-cost equipment, and low processing temperature. Thus, it can be advantageous for industrial sectors interested in materials with exceptional tribological properties.

Deformation and fracture properties of structural materials are greatly influenced by the factors like applied load, state of stress, and temperature. A precise prediction of the material properties of stainless steel at elevated temperature is necessary for determining the load-carrying capacity of structures under severe conditions. The present work reports the deformation and failure characteristics of 304L stainless steel subjected to combined laser heating and mechanical loading. The effect of main parameters on stress-strain, fracture characteristics, failure time, and temperature profile of specimens have been explored. Specimens were subjected to prescribed loading states, and then irradiated by a continuous wave fiber (1.08 µm) laser. The stress-strain curves indicated that the specimens experienced slight strain hardening in a specific temperature range prior to fracture. The specimen’s ultimate failure time is found to be reduced by increasing either laser power density or preload level. Fracture on a microscopic scale was predominantly ductile, comprising dimples as well as micro-void nucleation, growth, and coalescence. With the increase of laser power density, dimples rupture is the primary fracture mode, while with the increase of preload value, relatively more in-depth and severe deformation effects were observed. The description and characterization of 304L stainless steel failure under the simultaneous action of laser heating and tensile stress have been explored in detail.

The failure response of aluminum alloys (Al-6061 and Al-7075) under the condition of simultaneously pre-stressing and laser heating was investigated. Specimens were subjected to predetermined preloading states and then irradiated by continuous wave fiber (Yb) laser. For all specimens, it was found that the yield stress decreased with increasing laser power density. This implies that the load-bearing capacity of the specimens reduced under increased thermal or tensile loading. Consequently, the specimen’s failure time was shortened by increasing either laser power density or preloaded speed. For Al-6061, a remarkable reduction in failure time by the increase of laser power density is found. However, for Al-7075, under higher preloaded speeds, comparatively smaller impact of laser power density on the failure time is reported. Moreover, for Al-6061, relatively a more non-uniform variation in the average failure time with the increase of laser power density or preloaded speed is observed. The failure mode of Al-6061 turned from brittle to ductile at higher laser power densities; whereas for Al-7075, it changed from quasi-brittle to ductile. At higher preloaded speeds, a greater degree of melting and ablation phenomenon can be seen due to relatively higher temperatures and higher heating rates.

NiMnSn ferromagnetic shape memory alloys exhibit martensitic transformation at low temperatures, restricting their applications. Therefore, this is a key factor in improving the martensitic transformation temperature, which is effectively carried out by proper element doping. In this research, we investigated the martensitic transformation and magnetic properties of Ni₄₃Mn_46-x Sm_xSn₁₁ (x = 0, 1, 2, 3) alloys on the basis of structural and magnetic measurements. X-ray diffraction showed that the crystal structure transforms from the cubic L2₁ to the orthorhombic martensite and gamma (γ) phases. The reverse martensitic and martensitic transformations were indicated by exothermic and endothermic peaks in differential scanning calorimetry. The martensitic transformation temperature increased considerably with Sm doping and exceeded room temperature for Sm = 3 at. %. The Ni₄₃Mn₄₅SmSn₁₁ alloy exhibited magnetostructural transformation, leading to a large magnetocaloric effect near room temperature. The existence of thermal hysteresis and the metamagnetic behavior of Ni₄₃Mn₄₅SmSn₁₁ confirm the first-order magnetostructural transition. The magnetic entropy change reached 20 J·kg⁻¹·K⁻¹ at 266 K, and the refrigeration capacity reached ~162 J·Kg⁻¹, for Ni₄₃Mn₄₅SmSn₁₁ under a magnetic field variation of 0–5 T.

In this work, we study the structural, martensitic and magnetic characteristics of all-d-metal Ni35-xMn35+xCo15Ti15 (x = 0, 1, 2, 3) alloys. The x-ray diffraction analysis confirms that the alloy system crystallizes as 5M modulated and L10 non-modulated martensite with a small fraction of B2 austenite phase for x = 0. The proportion of austenite phase increases while the martensite phase decreases with increase in x, and B2 austenite phase becomes dominant for x = 3. Large endothermic/exothermic peaks with distinct thermal hysteresis in differential scanning calorimetry analysis indicate the martensitic/reverse martensitic transformations. The martensitic transformation temperature decreases considerably with increase in x. Thermal magnetization (M-T) curves show an abrupt variation in magnetization from weak magnetic martensite to ferromagnetic austenite near martensitic transformation temperature. M(H) loops measured at room temperature confirm the ferromagnetic behaviour of all the prepared samples. Isothermal magnetization (M-H) curves of Ni34Mn36Co15Ti15 at various temperatures show that the magnetic field can induce the magnetostructural transformation in this alloy. A magnetic entropy change of 11.3 JK-1kg-1 is observed at room temperature (290 K) in Ni34Mn36Co15Ti15 alloy.