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Hardness

Research outputs 2014 to 2021

Articles 1 - 5 of 5

Full-Text Articles in Engineering

Phase Transformation-Induced Improvement In Hardness And High-Temperature Wear Resistance Of Plasma-Sprayed And Remelted Nicrbsi/Wc Coatings, Jin Sha, Liang-Yu Chen, Yi-Tong Liu, Zeng-Jian Yao, Sheng Lu, Ze-Xin Wang, Qian-Hao Zang, Shu-Hua Mao, Lai-Chang Zhang Jan 2020

Phase Transformation-Induced Improvement In Hardness And High-Temperature Wear Resistance Of Plasma-Sprayed And Remelted Nicrbsi/Wc Coatings, Jin Sha, Liang-Yu Chen, Yi-Tong Liu, Zeng-Jian Yao, Sheng Lu, Ze-Xin Wang, Qian-Hao Zang, Shu-Hua Mao, Lai-Chang Zhang

Research outputs 2014 to 2021

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The remelting method is introduced to improve the properties of the as-sprayed NiCrBSi coatings. In this work, tungsten carbide (WC) was selected as reinforcement and the as-sprayed and remelted NiCrBSi/WC composite coatings were investigated by X-ray diffraction, scanning electron microscopy, hardness test and tribology test. After spraying, WC particles are evenly distributed in the coating. The remelting process induced the decarburizing reaction of WC, resulting in the formation of dispersed W2 C. The dispersed W2 C particles play an important role in the dispersion strengthening. Meanwhile, the pores and lamellar structures …


Particle Size-Dependent Microstructure, Hardness And Electrochemical Corrosion Behavior Of Atmospheric Plasma Sprayed Nicrbsi Coatings, Peng Sang, Liang-Yu Chen, Cuihua Zhao, Ze-Xin Wang, Haiyang Wang, Sheng Lu, Dongpo Song, Jia-Huan Xu, Lai-Chang Zhang Jan 2019

Particle Size-Dependent Microstructure, Hardness And Electrochemical Corrosion Behavior Of Atmospheric Plasma Sprayed Nicrbsi Coatings, Peng Sang, Liang-Yu Chen, Cuihua Zhao, Ze-Xin Wang, Haiyang Wang, Sheng Lu, Dongpo Song, Jia-Huan Xu, Lai-Chang Zhang

Research outputs 2014 to 2021

Particle size is a critical consideration for many powder coating-related industries since it significantly influences the properties of the produced materials. However, the effect of particle size on the characteristics of plasma sprayed NiCrBSi coatings is not well understood. This work investigates the microstructures, hardness and electrochemical corrosion behavior of plasma sprayed NiCrBSi coatings synthesized using different-sized powders. All coatings mainly consist of Ni, N3B, CrB, Cr7C3 and Cr3C2 phases. The coatings produced by small particles (50–75 μm) exhibit lower porosity (2.0 ± 0.8%). Such coatings show a higher fraction (15.5 vol.%) of the amorphous phase and lower hardness (700 …


Nanoindentation Characterization On Local Plastic Response Of Ti-6al-4v Under High-Load Spherical Indentation, Yan Wen, Lechun Xie, Zhou Wang, Liqiang Wang, Weijie Lu, Laichang Zhang Jan 2019

Nanoindentation Characterization On Local Plastic Response Of Ti-6al-4v Under High-Load Spherical Indentation, Yan Wen, Lechun Xie, Zhou Wang, Liqiang Wang, Weijie Lu, Laichang Zhang

Research outputs 2014 to 2021

After high-load spherical indentation treatment, the variations of hardness on the plastic zone of Ti-6Al-4V were investigated via nanoindentation method. The hardness within the center of plastic zone was measured by nanoindenter, and the magnitude decreased gradually along the depth, which were caused by the different extent of plastic deformation under the residual imprint. The microstructure of indentation were observed using scanning electron microscope (SEM) before and after surface etching, and the results showed that the microhardness revealed the average hardness of α and β phases of Ti-6Al-4V. The maximum hardness reached 6.438 GPa in the depth of 132 μm. …


Beta-Type Ti-Nb-Zr-Cr Alloys With Large Plasticity And Significant Strain Hardening, Syed F. Jawed, Chirag D. Rabadia, Y. J. Liu, L. Q. Wang, Y. H. Li, X. H. Zang, Laichang C. Zhang Jan 2019

Beta-Type Ti-Nb-Zr-Cr Alloys With Large Plasticity And Significant Strain Hardening, Syed F. Jawed, Chirag D. Rabadia, Y. J. Liu, L. Q. Wang, Y. H. Li, X. H. Zang, Laichang C. Zhang

Research outputs 2014 to 2021

A series of Ti-25Nb-8Zr-xCr (x = 0, 2, 4, 6, 8 wt%) alloys were designed based on DV-Xα cluster method and e=a-Δr diagram with an anticipation to obtain high plasticity and significant strain hardening. The designed alloys were produced through cold crucible levitation melting technique in order to effectively investigate their micro-structures and mechanical properties. The addition of Cr significantly enhances the β stability in the microstructures of the Ti-25Nb-8Zr-xCr alloys. Both yield strength and hardness of the studied alloys increase due to the effect of solid-solution strengthening. By contrast, the plasticity, maximum strength and strain hardening rate are influenced …


Synergistic Toughening Of Hard, Nacre-Mimetic Mosi2 Coatings By Self-Assembled Hierarchical Structure, Jiang Xu, Xiaoli Zhao, Paul Munroe, Zonghan Xie Jan 2014

Synergistic Toughening Of Hard, Nacre-Mimetic Mosi2 Coatings By Self-Assembled Hierarchical Structure, Jiang Xu, Xiaoli Zhao, Paul Munroe, Zonghan Xie

Research outputs 2014 to 2021

Like many other intermetallic materials, MoSi2 coatings are typically hard, but prone to catastrophic failure due to their low toughness at ambient temperature. In this paper, a self-assembled hierarchical structure that closely resembles that of nacre (i.e., mother of pearl) was developed in a MoSi2 -based coating through a simple, yet cost-effective, depostion technique. The newly formed coating is tough and can withstand multiple indentations at high loads. Key design features responsible for this remarkable outcome were identified. They include a functionally graded multilayer featuring elastic modulus oscillation, varying sublayer thickness and a columnar structure that are able to attenuate …