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2024 Vol. 29, No. 5
Published: 2024-10-15
Engineering and Technology
Theoretical Research
Review
Review
341
Research progress of friction reduction and anti-wear properties of surface texture of ceramic materials
ZHANG Jie, ZHANG Wei
DOI: 10.19976/j.cnki.43-1448/TF.2024054
Surface texture is an effective method of friction reduction and anti-wear of ceramic materials, which can reduce the friction factor during sliding and the loss caused by the wear of ceramics. In this work, the preparation, type, geometric parameters, and tribological mechanism of surface texture of ceramics are reviewed. Firstly, the main preparation methods (laser processing, reactive ion etching) for the surface texture of ceramics are introduced. Secondly, the effects of the types (convex dot, pit, groove, bionic texture, etc.) and geometric parameters (width, depth, area ratio, etc.) of surface textures on the tribological properties of ceramics are discussed. Subsequently, the tribological mechanisms of surface texture under dry sliding and lubrication conditions are analyzed, respectively. In the condition of dry sliding, the surface texture can trap the wear debris and reduce the contact area between the ceramics and the counterbody; in the condition of lubrication, the surface texture can improve the hydrodynamic pressure and wettability of the ceramics during sliding, both of which can improve the tribological properties of the ceramics. Finally, the current challenges and future research directions of the surface texture of ceramics are summarized and prospected.
2024 Vol. 29 (5): 341-352 [
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480
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353
Research progress of superhydrophobic coatings on metal materials
YANG Huan, ZHOU Zhangyan, MA Beiyue
DOI: 10.19976/j.cnki.43-1448/TF.2024065
Corrosion is common in metal materials, which limits the comprehensive utilization of metal resources. In recent years, inspired by the super-wetting phenomenon in nature, superhydrophobic coating, as a new metal protection mean, has been widely used. In this paper, the basic theory of superhydrophobic surface is expounded, and the recent development of superhydrophobic coatings on magnesium alloy, aluminum alloy, carbon steel, and titanium alloy is emphatically summarized, in order to provide reference and guidance for developing new functional materials, promoting related technological progress, and promoting cross-application in many fields.
2024 Vol. 29 (5): 353-361 [
Abstract
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92
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137
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Theoretical Research
362
Prediction of geometric dimensions and microstructure properties analysis of laser cladding Ni60 alloy coating on 316L stainless steel
LIU Lilan, YANG Fan, LI Sicong, WANG Shen, WANG Jiayi, WU Ziying
DOI: 10.19976/j.cnki.43-1448/TF.2024064
A theoretical prediction model for geometry dimensions of single-layer single-track coatings was established by analyzing the interactions between metal particles, substrate, and laser beam during the laser cladding process. Based on the experimental results of laser cladding Ni60 alloy coating on the surface of 316L stainless steel, the regression equations between the correction coefficients and the process parameters were achieved by multiple regression analysis. Therefore, the modified prediction model of geometric dimensions of single-layer single-track coatings was obtained by introducing the correction coefficients into the theoretical prediction model. The validation experiment was carried out under the conditions of the laser power, the scanning speed, and the powder feed rate of 1 750 W, 3.5 mm/s, and 0.099 g/s, respectively. The results show that the average relative errors between the modified prediction and experimental values of melt width, melt height, and melt depth are 0.85%, 2.47%, and 6.05%, respectively. The prediction accuracy of the modified prediction model is significantly improved compared with that of the theoretical prediction model. The results of the validation experiments show the feasibility of the modified prediction model. The Ni60 alloy coating is rich in hard phases, and its microhardness can be up to 3.4 times of that of 316L stainless steel substrate, and its wear rate is about 50% of that of substrate. The strengthening effect is remarkable.
2024 Vol. 29 (5): 362-372 [
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73
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83
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Engineering and Technology
373
Preparation and hydrothermal corrosion behavior of SiC coating by chemical vapor deposition
MAO Jian, CHEN Zhaoke, XU Zhennan, XIONG Xiang
DOI: 10.19976/j.cnki.43-1448/TF.2024034
SiC coating was prepared on high-purity graphite using chemical vapor deposition method, and hydrothermal corrosion experiment was conducted to study the relationship between chemical vapor deposition process, coating morphology and structure, and coating hydrothermal corrosion behavior. The results show that with the increase of dilution hydrogen flow rate, the average grain size of the coating decreases, the possibility of free Si appearing in the coating increases, and the resistance to hydrothemal corrosion gradually decreases. As the deposition temperature increases from 1 000 ℃ to 1 300 ℃, the crystallinity and average grain size of the coating first increases and then decreases. The maximum value is obtained at a deposition temperature of 1 200 ℃, and the coating structure and grain morphology remain intact after hydrothermal corrosion. As the temperature of the methyltrichlorosilane water bath increases, the average grain size of the coating increases. The coating prepared at a water bath temperature of 50 ℃ has the worst crystallinity and is the most severely corroded.
2024 Vol. 29 (5): 373-383 [
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61
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98
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384
Effects of counterpart materials on the current-carrying friction and wear properties of copper-graphite composites
WU Haihong, WANG Nenghui, ZHANG Lisong, YE Jiayu, WANG Chuanfeng, TU Youwang, KANG Xiao
DOI: 10.19976/j.cnki.43-1448/TF.2024063
To investigate the current-carrying friction and wear properties and underlying mechanisms of copper-graphite composites against different counterpart materials, two types of copper-graphite composites with varying graphite contents were prepared using the pressure sintering method. T2 copper, QCr0.8 copper-zirconium alloy, and hard gold-plated copper were selected as counterpart materials for current-carrying friction and wear tests. The microstructure, hardness, and friction and wear properties of the materials were examined using scanning electron microscopy, nanoindentation, surface profilometry, and pin-on-disk friction and wear test apparatus. The results show the average friction factors of the copper-graphite composites range between 0.4 and 0.5, the wear rates are on the order of 10
-13
m
3
/(N·m), the average voltage drop ranges from 0.7 V to 1.4 V, and the average electrical noise ranges from 0.2 mV to 0.7 mV when grinding with the three counterpart materials. Among these, the copper-graphite composite exhibits the best current-carrying friction and wear properties when paired with QCr0.8
2024 Vol. 29 (5): 384-395 [
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74
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396
Effects of surface modification of CNT on the mechanical and electrical properties of Cu-based composites
LI Yikun, ZHANG Yifan, ZHAO Wenmin, LIU Baixiong, ZHANG Xuehui, ZENG Longfei
DOI: 10.19976/j.cnki.43-1448/TF.2024060
Improving the dispersion of carbon nanotubes (CNT) in the Cu matrix and their interfacial bonding can effectively improve the properties of carbon nanotube enhanced Cu-based (CNT/Cu) composite material. This paper employed a one-step hydrothermal method to in situ generate carbonized polymer dots (CPD) on the surface of CNT for surface modification. Subsequently, CNT@CPD/Cu composites were prepared through a sintering process, and the mechanical and electrical properties of the composites were tested. The results indicate that after surface modification treatment, the structure of acid-treated CNT
1
is severely damaged, leading to a weakened enhancement effect. In contrast, after surface modification of non-acid-treated CNT
2
, CPD is loaded onto CNT
2
, which not only preserves the structural integrity of the CNT but also significantly improves their dispersion in the matrix and enhances the bonding with Cu. Furthermore, the addition of CPD and CNT effectively refines the Cu
2024 Vol. 29 (5): 396-402 [
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105
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67
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403
Preparation and properties of near-zero expansion SiC-based composites
LIU Qinghua, SUN Wei, ZHAN Zizhang, SHEN Yuzhu, ZHANG Hongbo, XIONG Xiang
DOI: 10.19976/j.cnki.43-1448/TF.2024037
In order to reduce the thermal expansion coefficient of SiC-based composites, this paper composited positive thermal expansion material SiC and negative thermal expansion material β-eucryptite to prepare a near-zero expansion SiC-based composite, and systematically studied the effects of β-eucryptite content on the porosity, microstructure, thermal and mechanical properties of the material. The results show that with the increase of β-eucryptite content, the porosity of the material decreases, the closed porosity increases, and the pores gradually change from irregular shape to spherical shape. Under the dual effect of porosity and β-eucryptite phase, the coefficient of thermal expansion of the material decreases. When the mass fraction of β-eucryptite increases from 20% to 50%, the average coefficient of thermal expansion of the material at 30-1 200 ℃ decreases from 2.30×10
-6
K
-1
to -0.80×10
-6
K
-1
, the porosity decreases from 36.9% to 12.9%, the thermal conductivity increases from 6.31 W/(m·K) to 8.85 W/(m·K), and the compressive strength increases from 176.3 MPa to 375.6 MPa.
2024 Vol. 29 (5): 403-410 [
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80
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411
Deformation recrystallization behavior and grain size model of Ti-5Al-3Mo-3Cr-1Zr-0.1Si alloy
LI Chao, FAN Kai, ZHU Xuefeng, ZHAN Xiaodong, ZHU Hongchang
DOI: 10.19976/j.cnki.43-1448/TF.2024062
In this paper, Ti-5Al-3Mo-3Cr-1Zr-0.1Si alloy was deformed in two-phase zone and annealed in single-phase zone to study the effects of deformation temperature, degree of deformation, and deformation-annealing articulation on the static recrystallisation behaviour of the alloy, and established a model for the correlation between the deformation temperature and the β grain size after annealing. The results show that the low deformation temperature is conducive to the β grain refinement. This is attributed to the increase of α phase content at low deformation temperature, which in turn increases the deformation distortion energy of β matrix and promotes the recrystallized nucleation of β phase. The average grain size of the alloy after annealing decreases with the increase of deformation degree. When the deformation degree exceeds 40%, the β grain average size gradually tends to stabilize, about 136 μm. The cooling rate after the deformation also affects the grain size after annealing, and the faster the cooling rate is, the larger the β grain size is. When the alloy is heated directly to the single-phase zone for annealing without cooling after pre-deformation, the β grains are uniformly refined.
2024 Vol. 29 (5): 411-422 [
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62
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122
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