Surface Engineering
Công bố khoa học tiêu biểu
Sắp xếp:
Comparative responses of welded joints to surface mechanical attrition treatment and shot peening Responses of welded joint of carbon steel to surface mechanical attrition treatment (SMAT) and shot peening (SP) were investigated. Experimental evidences showed that the microstructure of treated surface in the welded joint by means of SMAT was characterised by nanometre grains of about 13·6 nm in size and that of SP was characterised by highly dense dislocation configuration. The similar microhardness profiles with different peak values in the top surface were observed for three typical zones of welded joints processed by SMAT and SP. Compared with as welded specimens, SMAT and SP processes have improved the fatigue strength by as much as 61 and 36·3% respectively based on fatigue life 2×106 cycles. The observed enhanced fatigue behaviours of the welded joint processed by SMAT and SP should be attributed to the combined influences of compressive residual stress, work hardening, nanostructure and elimination of microdiscontinuities in the vicinity of welded joints.
Surface Engineering - Tập 25 Số 1 - Trang 15-20 - 2009
The effect of duty cycle on the mechanical and electrochemical corrosion properties of multilayer CrN/CrAlN coatings produced by cathodic arc evaporation
Surface Engineering - Tập 37 Số 2 - Trang 253-262 - 2021
Microstructural studies of e-beam evaporated alumina thin films Alumina thin films of different thicknesses, e.g. 90, 120 and 150 nm, were grown on SS304 thin foil by electron beam evaporation technique. The films were post-heat treated at 500, 700 and 800°C in air and subsequently characterised by X-ray diffraction, atomic force microscopy, field emission scanning electron microscopy and X-ray photoelectron spectroscopy. The effects of thicknesses and post-heat treatment on microstructure have been studied. The deposited alumina film was almost stoichiometric. The alumina film of the lowest thickness, i.e. 90 nm post-heat treated at 700°C, showed preferential growth of nanorods and irregular polygonal nanostructures with random orientation.
Surface Engineering - Tập 30 Số 8 - Trang 594-599 - 2014
Ti/Cr(III) conversion coating on aluminium foil for lithium-ion battery package
Surface Engineering - Tập 37 Số 3 - Trang 365-372 - 2021
Nitriding of Stainless Steelin Ammonia: I Phase Distribution and Microstructure The compound layer of iron nitrides (white layer) and the diffusion layer formed during the nitriding of an austenitic stainless steel have been investigated by a combination of optical and electron microscopy and X-ray powder diffraction. The mechanical behaviour of the nitrided surface is controlled by the microstructure, which is shown to be dictated by the nitriding temperature and cooling rate from that temperature. The results provide a complete description of the phase distribution in the nitrided case and indicate the nitriding conditions required to achieve a wide range of properties, from surface hardening to deliberate embrittlement.
Surface Engineering - Tập 1 Số 2 - Trang 114-124 - 1985
Plasma Nitriding of Stainless Steel using Continuous and Pulsed RF Glow Discharge A novel radio frequency (rf) plasma technique for nitriding engineering steels is described whichproduces a surface layer of exceptional hardness in extremely short nitriding times. The sample does not form part of the primary electrical circuit, as is the case, with de plasma methods, and the temperature at the metal surface is controlled by a variable pulsed mode operation of the inductively coupled nitrogen plasma. The rate of nitriding is compared to those obrained by conventional ammonia nitriding and by de plasma methods. The rapid rates of layer growth observed with the rf plasma are discussed in terms of an interstitial–vacancy coupled diffusion model. The results demonstrate the feasibility of a rapid and flexible process for nitriding all grades of engineering steels.
Surface Engineering - Tập 4 Số 2 - Trang 150-154 - 1988
Study of methanol electro-oxidation on Ni and Ni–Pt/carbon paper electrodes for direct methanol fuel cell applications This study deals with the oxidation of methanol in alkaline media. For this purpose, first nickel and nickel–platinum particles were deposited on carbon paper substrates by using electroplating with galvanic deposition method. Then the morphology of the metal particle coatings on the carbon paper was studied by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The catalytic properties of the electrodes for methanol oxidation were studied using electrochemical methods such as cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). The results showed higher catalytic activity of the Ni–Pt/carbon paper electrode compared with the Ni/carbon paper electrode. Therefore, Ni–Pt/carbon paper electrode is a good candidate as an anode for direct methanol fuel cells.
Surface Engineering - Tập 30 Số 4 - Trang 263-267 - 2014
Electroplating of Pt–Ni–Cu nanoparticles on glassy carbon electrode for glucose electro-oxidation process Platinum and nickel–copper nanoparticles were electrodeposited on glassy carbon electrode (GCE) by using cyclic voltammetry (CV)-based electroplating technique. Morphology and chemical composition of the newly designed electrode was studied via scanning electron microscope, energy dispersive X-ray and elemental mapping analysis. This electrode was eventually employed to electro-oxidation of glucose using CV, chronoamperometry (CA) and electrochemical impedance spectroscopy techniques. Pt–Ni–Cu/GCE is capable of electro-oxidation of glucose at a low potential and generating high peak current density. The results of CV and CA revealed the high catalytic activity of the Pt–Ni–Cu/GCE and steady-state activity for glucose electro-oxidation. Compared to the other electrodes reported in the previous literature, Pt–Ni–Cu/GCE shows a better potential as an anode. Low electrochemical charge transfer resistance ( Rct ) is of particular advantages for the Pt–Ni–Cu/GCE. This electrode is a good choice as an anode for application in direct glucose alkaline fuel cells.
Surface Engineering - Tập 35 Số 2 - Trang 128-134 - 2019
Research status of magnesium alloys by micro-arc oxidation: a review Magnesium and its alloys are fascinating candidates for biodegradable implants due to their suitable mechanical properties, biodegradability and biocompatibility. However, the rapid corrosion rate, generation of a large amount of hydrogen gas and increase in local pH of the body fluid limit their potential biomedical applications. Various techniques, including alloying, mechanical processing and surface treatment, have been used to reduce the corrosion rate of materials. Surface treatment is one of the widely used techniques to improve the corrosion resistance of the Mg alloys. Compared to other surface modification processes, micro-arc oxidation can provide good adherent, hard, scratch-resistant, wear-resistant, and corrosion-resistant coatings on magnesium alloys. This article mainly reviews the influence of key relatively process parameters, such as electrolytic composition and presence of additives. Normally, electrolytic system and additives can improve the corrosion behaviour of magnesium alloys using appropriate concentration. The future prospects are summarised as well.
Surface Engineering - Tập 33 Số 10 - Trang 731-738 - 2017
Rake and Flank Wear Mechanisms of Coated Cemented Carbides A series of commercially available cemented carbides coated with single or composite layers of TiC, TiN, and Al2 O3 were used to cut three types of steel, En 8 (080M40), En9 (070M55), and En24 (817M40). For comparison, two uncoated cemented carbides and some Al2 O3 -ceramic inserts were also tested. The worn surfaces were examined using optical and scanning electron microscopy techniques and tool/work interfacial conditions were evaluated from ‘quick stop’ experiments and tool temperature estimates. By linking this information with observed wear rates, various rake and flank wear mechanisms are proposed.
Surface Engineering - Tập 1 Số 1 - Trang 43-58 - 1985
Tổng số: 12
- 1
- 2