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This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/00368790510614163. When citing the article, please cite: B.S. Yilbas, M. Sunar, Z. Qasem, B.J. Abdul Aleem, S. Zainaulabdeen, (2005), “Study into mechanical properties of TiN coating on Ti-6Al-4V alloy through three-point bending tests”, Industrial Lubrication and Tribology, Vol. 57 Iss: 5, pp. 193 - 196.

To examine the mechanical properties of TiN PVD coated Ti‐6Al‐4V alloy through three‐point bending tests.

Ti‐6Al‐4V alloy is cut in size and polished and cleaned chemically before TiN PVD coating process. INSTRON three‐point bending equipment is used to conduct the bending tests for TiN coated and uncoated workpieces. During the tests, the load and displacement characteristics were recorded. The tests were terminated when the coating failed. Micrographs of surface and crack sites were obtained by SEM.

Coating failure occurs due to shearing effect on the tensile surface. The spalling and buckling of the coating on the compressive surface are observed. The compressive stress generated on the top surface (where the indent is in contact) did not cause adhesive failure of the coating. Moreover, cohesive cracks occur on the tensile surface of the coating. The crack ledge under the action of shear stress appears on the tensile surface of TiN coating and multi cracking of coating is resulted. The crack spacing is small indicating sliding and splitting separation between the adjacent columns in the coating.

The tests can be extended to include the duplex treated workpieces such as the heat treatment of surface prior to TiN coating. This enhances the interface properties of the coating and base alloy.

The results can be used to assess the TiN coating applications in cutting tools, particularly drill bits and punches.

This paper provides information on mechanical behavior of TiN coating when subjected to bending force and offers practical help for the researchers and scientists working in the coating area.

Metal forming through punching finds wide interest in industry. The punch life and the end product quality depend on the punch and workpiece properties as well as punching conditions. Recently, TiN coating of the punch surface has reported to improve considerably the tool life and the end product quality. This is because of the high hardness and low friction coefficient of TiN coating. In the present study, the wear properties of sheared edges punch is investigated through SEM micrograph and EDS analysis. Mild steel is selected as workpiece material while the punch material is cold‐work tool steel (A2). The punch surface is coated with TiN (PVD) and an uniform coat thickness is assured. It is found that the wear mechanism is governed by adhesive and abrasive wear through shearing. The TiN coating protects the punch surface in the initial cycles of the punching process. As the punching cycle progresses, local defects in TiN coating are observed, i.e. coating is locally worn away.

The eastern coast of Saudi Arabia has one of the most corrosive environments in the world. Dhahran is therefore an ideal location for the study of atmospheric corrosion. One out of every seven cars in the region is corroded. The atmosphere is contaminated by SO₂ and a high concentration of suspended particulate matter (SPM) containing sand, salt and carbon particles, exceeding the World Health Organization (WHO) and Middle East Environmental Protection Agency (MEPA) limits most of the time. Corrosion proceeds in the Dhahran atmosphere at a R.H. as low as 40 per cent. At locations close to the sea (1.5 Km), β‐FeOOH is the major corrosion product and α‐ and γ‐FeOOH with some aluminates, silicates and hydrocarbons the minor products. At a location remote from the sea α‐ and γ‐FeOOH are found to be the major corrosion products as shown by XRD and FTIR spectroscopy. The concentration of hydrogen ions, chloride ions and SO₂ appears to control the corrosion process during the initial exposure period up to one year and the adsorption of anions on the corrosion product films in the later period.

The laser nitriding process is involved with high temperature heating and high cooling rates. This, in turn, results in high levels of thermal stresses in the heated region. Moreover, the residual stress in the heated region remains high after the completion of the heating process, which limits the application of the laser nitriding process. The purpose of this paper is to investigate thermal stresses development and residual stress levels in the nitrided region.

The microstructural changes and residual stress development in the laser gas‐assisted nitrided zone are examined. Finite element modeling is carried out to predict temperature and stress fields in the laser nitrided layer. The indentation tests and X‐ray diffraction (XRD) technique are used to determine the residual stress levels while previously derived analytical formula is used to predict the residual stress levels in the nitrided region.

The residual stress predicted attains values within 230 MPa, which remains almost uniform in the nitrided layer, except in the surface region. In this case, residual stress reduces slightly due to the low temperature gradient developed in this region and the unconstrained expansion of the free surface. When comparing the residual stress predicted with the measurement results as obtained from the XRD technique as well as the indentation tests, all the results are in reasonably good agreement. The small discrepancies between the experimental data and predictions are attributed to the assumptions made in the model study and the measurement errors.

The depth of nitrided layer is limited 60 μm. This limits the applicability of the coating for high wearing rates.

The nitrided surface improves the surface properties of steel, which can be used in industry more efficiently.

The paper describes an original model study on stress formation, an experiment for surface characterization and estimation of residual stress formation and contains new findings.

Laser welding under high power, high degree of automation and high production rate is extremely advantageous in automotive application. Super austenitic stainless steel is the preferable material for high corrosion resistance requirements. These steels are relatively cheaper than austenitic stainless steel and it is expensive than nickel base super alloys for such applications. The main purpose of this paper is to present the investigations of the microstructure and mechanical properties of super austenitic stainless steel butt joints made by 3.5 kW cooled slab CO₂ laser welding using different shielding gases such as argon, nitrogen and helium.

The tensile and impact tests were performed and the fractured surfaces were analyzed by scanning electron microscope. The hardness across the joint zone was measured. The X‐ray diffraction technique was used to analyze the phase composition. The microstructure of the laser welds were analyzed through optical microscopy.

The tensile sample fractures indicate that the specimen fails in a ductile manner under the action of tensile loading. The impact fracture surfaces of the different shielding gas laser welded joints show mixed mode fractures, that is, ductile and cleavage fractures. The hardness values of the Helium shielded laser joints in the weld metal regions are much higher than the others.

There is no limitation, except for the availability of the high beam power laser welding machine.

The only practical implication is the laser welding shop hazard during the experiment.

Social implication is limited. The only hazard during the laser welding is that it may affect human body tissues.

The research work described in the paper is original.

A model study of laser heating process including phase change and molten flow in the melt pool gives physical insight into the process and provides useful information on the influence of melting parameters. In addition, the predictions reduce the experimental cost and minimize the experimental time. Consequently, investigation into laser control melting of the titanium alloy becomes essential. The purpose of this paper is to do this.

Laser repetitive pulse heating of titanium surface is investigated and temperature field as well as Marangoni flow in the melt pool is predicted using finite volume approach. The influence of laser scanning speed and laser pulse parameter (defining the laser pulse intensity distribution at the workpiece surface) on temperature distribution and melt size is examined. The experiment is carried out to validate temperature predictions for two consecutive laser pulses.

The influence of laser scanning speed is significant on the melt pool geometry, which is more pronounced for the laser pulse parameter β=0. Temperature predictions agree with the thermocouple data obtained from the experiment.

Although temperature dependent properties are used in the simulations, isotropy in properties may limit the simulations. The laser canning speed is limited to 0.3 m/s, which is good for surface treatment process, but it may slow for annealing treatments.

The results are very useful to capture insight into the melting process. In addition, the influence of laser scanning speed and laser pulse intensity distribution on the melt formation in the surface vicinity is well presented, which will be useful for those working on laser surface treatment process.

The work is original and findings are new, which demonstrate the influence of laser parameters on the melt pool formation and resulting Marangoni flow.

The prevalence of crises is a real phenomenon that demands proper planning and implementation of measures to preempt and curb its consequences on both national economies and business operations. Crisis is one of the concepts that cannot be overlooked, pervasive in nature, and does not necessarily denote negativity. Crisis is no longer an unusual, arbitrary, or minor characteristic of today's business environment. As far as the business environment continues to be volatile and unpredictable, it is unlikely that business organizations would be free from crises. Crises are noted to be a vital part of a business context and can serve as an avenue for positive change and creativity if the right tools and techniques are employed to properly manage them. On the other hand, crises can jeopardize the continued existence of the organization and obstruct the achievement of its goals. Thus, the debilitating ramifications of crises on business growth, survival and overall success calls for adoption of sustainable crisis management approaches in this new business world order that is framed by Industry 5.0, digitalization, and green business practices. The primary purpose of this article is to establish how modern crisis management methods could lead to sustainable organizational development. The current study departs from existing studies in the literature by systematically presenting methods to anticipate, solve, and transform business crises into advantage. The chapter also throws light on how organizations should manage business crises that may well be accelerated by Industry 5.0 and its components; digitalization and sustainable development.

The main purpose of the present study was to evaluate the metallurgical and mechanical properties of dissimilar metal friction welds (FWs) between aluminium and type 304 stainless steel.

One of the manufacturing methods used to produce parts made from different materials is the FW method. Therefore, in the present study, austenitic stainless steel and aluminium parts were joined by FW. Tensile, fatigue and notch-impact tests were applied to FW specimens, and the results were compared with those for the original materials. Microstructure, energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analysis and hardness variations were conducted on the joints.

It was found from the microstructure and XRD analysis that inter-metallic phases formed in the interface which further caused a decrease in the strength of the joints.

In this study, the rotation speed was kept constant. The effects of the rotation speed on the welding quality can be examined in future. It is important to note that the FW process was successfully accomplished in this study although it was particularly difficult to obtain the weld due to the large deformations at the interface.

Low-density components such as aluminium and magnesium can be joined with steels owing to being cost-effective in industry. Application of classical welding techniques to such materials is difficult because they have different thermal properties. Their welding plays a key part in industrial quality and process control, in the efficient use of energy and other resources, in health and safety. Then, this study will contribute for welded, brazed and soldered materials.

The main value of this paper is to contribute and fulfill the influence of the interface on properties in welding of various materials that is being studied so far in the literature.

This study aims to assess the mediating effect of sustainable competitive advantage (SCA) on the relationship between organisational innovativeness (OI) and performance of small- and medium-sized enterprises (SMEs) operating in Konya, Turkey.

A survey method is used to collect the necessary data for this research. A total of 264 respondents from 83 SMEs partook in the study. In choosing the sample size, both purposive sampling and simple random techniques are used. The data gathered are analysed using SPSS program and Hayes PROCESS macro v.3.4.1.

The results of the analyses reveal that OI has a statistically significant positive effect on SCA and firm performance (FP). Moreover, SCA is found to have a mediating effect on the relationship between OI and FP.

Policymakers and management of SMEs need to show great commitment to innovativeness and relate it to SCA to create superior customer value, thereby leading to a holistic and long-term FP.

This study brings to the fore empirical evidence on how SCA serves as a mediator between OI and FP. It also contributes to the literature by focusing on three distinct but related variables. The study makes theoretical contribution by highlighting the role of the resource-based theory in enhancing business performance and SCA through strategic internal resources and innovative activities.