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1 – 2 of 2Jiabo Chen, Xiaokai Guo, Hao Liu, Xuantong Lv, Shichuan Fan, Liankui Wu, Fahe Cao and Qingqing Sun
This study aims to discuss the influences of surface severe plastic deformation (S2PD) on the electrochemical corrosion, pitting corrosion, intergranular corrosion, stress…
Abstract
Purpose
This study aims to discuss the influences of surface severe plastic deformation (S2PD) on the electrochemical corrosion, pitting corrosion, intergranular corrosion, stress corrosion cracking of aluminum (Al) alloys and attempt to correlate the microstructural/compositional changes with the performances.
Design/methodology/approach
This study provides a novel gradient design of structure/composition caused by S2PD for the purpose of enhancing Al alloys’ corrosion resistance.
Findings
S2PD has a significant effect on corrosion behavior of Al alloys through tuning the grain size, residual stress, composition, grain boundary phase and second phase particle distribution.
Originality/value
Although Al alloys are known to form a protective Al2O3 film, corrosion is a major challenge for the longevity of Al structures across numerous industries, especially for the infrastructures made of high-strength Al alloys. Traditional strategies of improving corrosion resistance of Al alloys heavily relied on alloying and coatings. In this review, gradient design of structure/composition caused by S2PD provides a novel strategy for corrosion protection of Al alloys, especially in the enhancement of localized corrosion resistance.
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Lili Zhu, Jinxu Bai, Xu Liang and Maojin Jia
The purpose of this paper is to calculate the meshing stiffness of nutation face gear considering the roughness, establish the calculation method of time-varying meshing stiffness…
Abstract
Purpose
The purpose of this paper is to calculate the meshing stiffness of nutation face gear considering the roughness, establish the calculation method of time-varying meshing stiffness of rough tooth surface and analyze the influence of roughness, load and other factors on the meshing stiffness of tooth surface.
Design/methodology/approach
The Weierstrass–Mandelbrot (W-M) function in the Majumdar–Bhushan model is used to characterize the rough contact line of the tooth surface, the normal height and radius of the micro convex body are calculated and the contact flexibility of the contact point of the tooth surface is obtained. The contact flexibility and the bending shear deformation flexibility obtained previously are substituted into the improved deformation compatibility equation for iterative calculation, and the time-varying meshing stiffness of the nutation face gear considering the roughness is obtained.
Findings
Compared with ABAQUS finite element simulation results, it is found that the meshing stiffness curve of rough tooth surface is more gentle than that of smooth tooth surface, the meshing stiffness value is smaller and the meshing stiffness change is smaller at the position where the number of gear teeth coincide changes.
Originality/value
In the process of calculating contact deformation, the fractal theory W-M function is used to characterize the contact line of the rough nutation face gear, and the deformation coordination condition considering roughness is improved. Therefore, the method of time-varying meshing stiffness considering roughness can obtain more accurate results, which provides theory and data for the subsequent dynamics analysis of the nutation face gear transmission.
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