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For the purpose of saving nickel, this study aims to develop new duplex stainless steel cored wires suitable for wire arc additive manufacturing (WAAM) with the addition of nitrogen.

The effect of nitrogen content on the microstructure and mechanical properties of the thin-walled deposits is investigated in detail.

The microstructure of thin-walled deposits mainly consists of austenite, ferrite and secondary austenite. With increasing nitrogen content, the austenite in the deposited metals increases. The austenite proportion in the bottom region is more than that in the top region of the deposited metals. The χ phase is randomly distributed at the grain boundaries and within ferrite. The σ phase is mainly precipitated at ferrite and austenite grain boundaries. With increasing nitrogen content, the tensile strength of the deposited metals increases, but the impact toughness of the deposited metals deteriorates.

This study proposes new duplex stainless steel cored wires for WAAM, which realizes the objective of saving nickel.

The air‐breathing hypersonic vehicle (AHV) includes intricate inherent coupling between the propulsion system and the airframe dynamics, which results in an intractable nonlinear system for the controller design. The purpose of this paper is to propose an H∞ control method for AHV based on the online simultaneous policy update algorithm (SPUA).

Initially, the H∞ state feedback control problem of the AHV is converted to the problem of solving the Hamilton‐Jacobi‐Isaacs (HJI) equation, which is notoriously difficult to solve both numerically and analytically. To overcome this difficulty, the online SPUA is introduced to solve the HJI equation without requiring the accurate knowledge of the internal system dynamics. Subsequently, the online SPUA is implemented on the basis of an actor‐critic structure, in which neural network (NN) is employed for approximating the cost function and a least‐square method is used to calculate the NN weight parameters.

Simulation study on the AHV demonstrates the effectiveness of the proposed H∞ control method.

The paper presents an interesting method for the H∞ state feedback control design problem of the AHV based on online SPUA.

The purpose of this paper is to present some numerical methods based on different time stepping and space discretization methods for the Allen‐Cahn equation with non‐periodic boundary conditions.

In space the equation is discretized by the Chebyshev spectral method, while in time the exponential time differencing fourth‐order Runge‐Kutta (ETDRK4) and implicit‐explicit scheme are used. Also, for comparison the finite difference scheme in both space and time is used.

It is found that the use of implicit‐explicit scheme allows use of a large time‐step, since an explicit method has less order of accuracy as compared to implicit‐explicit method. In time‐stepping the proposed ETDRK4 does not behave well for this special kind of partial differential equation.

The paper presents some numerical methods based on different time stepping and space discretization methods for the Allen‐Cahn equation with non‐periodic boundary conditions.

The purpose of this paper is to study friction and wear properties of three types of steels against paper-based friction disc, including 65Mn, 20#steel and 30CrAl, so as to obtain the appropriate working conditions for different friction materials in the transmission system.

Based on actual working conditions, pin-on-disc tests are conducted on a universal material tester. The two evaluation indexes, including average friction coefficient and variation coefficient, are introduced to analyze the different friction properties among three types of steel. Furthermore, the temperature-dependent wear pattern and wear depth are subsequently studied.

The results show that 65Mn is more suitable for working under heavy load and low velocity, but 30CrAl and 20#steel are suitable for working under light load and high velocity. Moreover, wear primarily occurs on paper-based material and peaks at about 325.

This research of different materials and friction property for friction pairs is helpful to improve the performance and prolong the service life of transmission systems.

Suitable working conditions of different friction materials are obtained, and the correlation between wear and decomposition in high temperature is verified.

This study aims to examine the relationship between renqing and purchase intentions and the mechanism of its impact in the Chinese business-to-business (B2B) context.

Renqing in China has played an important role in business relationships and has been receiving increased attention in both practice and theory. However, little is known about whether it can influence purchase intentions in a rational B2B condition. This research aims to examine the relationship between renqing and purchase intentions and the mechanism of its impact in the Chinese B2B context. Based on a survey of 1,010 industry buyers from 468 Chinese downstream buyer companies, the empirical findings indicate a positive relationship between renqing and purchase intentions and the mediating role of long-term orientation (LTO) for increasing purchase intentions. In addition, this study also finds that product involvement (PI) has a negative moderating effect on the relationship between renqing and purchase intentions, which means that renqing has a big positive effect on purchase intentions in low PI conditions. The results highlight several implications for B2B companies that sell products to Chinese enterprises.

The empirical findings indicate a positive relationship between renqing and purchase intentions and the mediating role of LTO for increasing purchase intentions. In addition, this study also finds that PI has a negative moderating effect on the relationship between renqing and purchase intentions, which means that renqing has a big positive effect on purchase intentions in low PI conditions.

First of all, by answering the research question, this study shows that renqing has a positive effect on purchase intentions in Chinese B2B context. Second, this study elucidates the influence mechanism of renqing on purchase intention and identifies the mediating effect of LTO and the moderating effect of PI.

The purpose of this paper is to examine the impact of inter-group conflicts on the trust toward the acquirer and then further on cooperation intention after acquisitions in cross-border mergers and acquisitions (M&As), in the lens of the social classification theory. Two types of conflicts (realistic conflicts and symbolic conflicts) and a mediating mechanism (trust toward the acquirer) exhibit different effects on cooperation intention. The research further examines two moderating coping strategies (localizing management and assigning trustworthy expatriate managers) and tests their effectiveness in promoting trust toward the acquirer and increasing cooperation intention in cross-border M&As.

The research hypotheses were empirically tested in the context of post-acquisition of Chinese companies' cross-border M&As. In total, 600 questionnaires were provided to the research participants of 37 acquired firms/units from advanced economies of 12 Chinese companies, and 209 valid questionnaires were collected (the response rate is 34.83%). Confirmatory factor analysis was conducted to verify data validity and hierarchical multiple regression analyses were employed to test relational and moderating effects.

This research demonstrates that both realistic and symbolic conflicts can reduce the intention to cooperate, but the latter does not have a significant influence. The results also uncover that whether employees from acquired firms trust in their acquirers mediates the relationship between realistic conflicts and cooperation intention. Moreover, management localization (a measurement of whether local/original managers are retained with a high degree of freedom and autonomy after M&As) and trustworthiness of expatriate managers (a measurement of whether the assigned expatriate managers is trustworthy) positively moderate the relation between realistic conflicts and trust toward the acquirer. In addition, trust toward the acquirer mediates the interaction of realistic conflicts and management localization on the cooperation intention of the acquirers' employees.

This study examines how inter-organizational conflicts influence trust toward the acquirer and then cooperation intentions in the context of Chinese companies' M&A behavior of targets from developed countries and gain supportive evidence, which enriches the literature on the management of international M&As. By introducing two management localization and trustworthiness of expatriate managers into the model, the research deepens our knowledge of how to build trust toward the acquirer in cross-border M&As.

This paper aims to explore the effect of automatic transmission fluid (ATF) temperature on the dynamic friction-wear properties of the friction component in a wet multi-disc clutch during the running-in process.

The running-in evolution was explored in terms of global friction performance and instantaneous friction characteristics. The variation of friction torque of the initial 300 engagement cycles was obtained by wet-clutch tests. Finally, an optical microscope was used to detect the wear mechanism of friction surfaces.

The ATF temperature showed a significant effect on the friction-wear performance in the clutch running-in process. The mean coefficient of friction decreased with the increase of the ATF temperature and decreased rapidly in the approximately initial 60 clutch engagements. The higher the ATF temperature was, the thinner the ATF film was, and more asperity summits were cut, thus leading to a smoother surface. Considering the slightly instantaneous friction fluctuation and the wear performance, a proper ATF temperature is necessary.

The results provide theoretical guidance for selecting the optimal ATF temperature during the running-in process.

This paper aims to explore the influence of applied pressure on the tribological properties of the friction component in a wet multi-disc clutch during the running-in process.

The running-in evolutionary was explored in terms of global friction performance. The variation of friction torque and mean COF of the initial 300 engagement cycles was obtained by full-scale tests. Finally, an optical microscope was used to detect the wear characteristics of friction surfaces.

The applied pressure showed a significant influence on the tribological behaviors of wet clutches during the running-in process. The mean COF decreased and then increases with the increase of the applied pressure. A higher applied pressure contributed to more asperity summits being sheared, thus resulting in a smoother surface. Considering a suitable wore performance, properly applied pressure is necessary.

The results provide theoretical guidance for selecting the optimal applied pressure in the running-in of wet clutches.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2022-0256/

The purpose of this study is to explore how tobacco manufacturing companies can improve their sustainability performance via effective supplier relationship management (SRM).

This study has adopted a single case study of an international tobacco company. The primary data involved semi-structured interviews with participants from the case company who are familiar with sustainable SRM in the tobacco industry and are engaging in various techniques to improve sustainability performance.

The drivers for sustainable SRM commonly identified in literature are observable within the case company. There is also clear evidence of integrating sustainability in its SRM processes. However, the perception of sustainability as a requirement to meet stringent regulations limits its scope and drive in pursuing sustainable SRM. It has also limited supplier sustainability evaluation and performance metrics. Furthermore, the findings of this paper reinforce the importance of a procurement team’s ability to work with other functional teams in implementing sustainable SRM. The findings also contribute to the emerging literature on the impact of sustainability on supplier segmentation and multi-tier supplier management.

This study provides insight into the varying SRM methods used in the tobacco industry to ensure compliance and improve sustainability performance. However, further research is required to explore the generalisability of the findings of this study derived from a single case study.

The tobacco industry is an under-researched industry, particularly in terms of sustainable operations and supply chain management practices. The findings of this study seem to be relevant to those comparable industries with stringent regulations as well.

The metallic alloys and their components fabricated via laser powder bed fusion (LPBF) suffer from the microvoids formed inevitably due to the extreme solidification rate during fabrication, which are impossible to be removed by heat treatment. This paper aims to remove those microvoids in as-built AlSi10Mg alloys by hot forging and enhance their mechanical properties.

AlSi10Mg samples were built using prealloyed powder with a set of optimized LPBF parameters, viz. 350 W of laser power, 1,170 mm/s of scan speed, 50 µm of layer thickness and 0.24 mm of hatch spacing. As-built samples were preheated to 430°C followed by immediate pressing with two different thickness reductions of 10% and 35%. The effect of hot forging on the microstructure was analyzed by means of X-ray diffraction, scanning electron microscopy, electron backscattered diffraction and transmission electron microscopy. Tensile tests were performed to reveal the effect of hot forging on the mechanical properties.

By using hot forging, the large number of microvoids in both as-built and post heat-treated samples were mostly healed. Moreover, the Si particles were finer in forged condition (∼150 nm) compared with those in heat-treated condition (∼300 nm). Tensile tests showed that compared with heat treatment, the hot forging process could noticeably increase tensile strength at no expense of ductility. Consequently, the toughness (integration of tensile stress and strain) of forged alloy increased by ∼86% and ∼24% compared with as-built and heat-treated alloys, respectively.

Hot forging can effectively remove the inevitable microvoids in metals fabricated via LPBF, which is beneficial to the mechanical properties. These findings are inspiring for the evolution of the LPBF technique to eliminate the microvoids and boost the mechanical properties of metals fabricated via LPBF.