scholarly journals Preparation and the Mechanical and Tribological Properties of Laser Cladding Coating

2021 ◽  
Vol 2083 (2) ◽  
pp. 022067
Author(s):  
Xin Zhou ◽  
Yanjun Wang ◽  
Lei Liu ◽  
Xingju Guo

Abstract laser cladding of snsbcu based alloy coating on GCr15 steel substrate was carried out by using lam-400s powder feeding metal printer. The hardness, friction coefficient and microstructure of the coating were tested by Vickers hardness tester, friction and wear tester, metallographic microscope and scanning electron microscope. The effects of laser cladding parameters on the dilution ratio, hardness and friction coefficient of the sample were studied; With the increase of laser power, the hardness of the coating is improved, and the hardness distribution is more uniform; The friction coefficient of the coated sample decreases greatly compared with that of the substrate.

2019 ◽  
Vol 46 (5) ◽  
pp. 0502001
Author(s):  
陈菊芳 Chen Jufang ◽  
李小平 Li Xiaoping ◽  
薛亚平 Xue Yaping

2019 ◽  
Vol 25 (3) ◽  
pp. 252-258
Author(s):  
Geng TIANYUAN ◽  
Cunshan WANG

Ni-based alloy cladding layers with different graphene sheet additions were prepared by laser cladding on the 40CrNi2Si2MoV steel substrate. The influence of the graphene sheet on the microstructure and properties of the cladding layers was investigated. The results show that owing to the diffusion-reaction dissolution, the graphene sheet addition does not bring a corresponding change in the phase constitutions of the cladding layers, i. e., the cladding layers are still composed of γ-Ni, Ni3B, and M7C3 phases. But what has changed is that the solidified structure is refined, and the volume fractions of the eutectic and the carbide are increased with the increase of graphene sheet addition. As a result, the hardness and the wear resistance of the cladding layers gradually increase, whereas the friction coefficient firstly decreases and then increases, with the lowest friction coefficient obtained at 0.5 vol.% graphene sheet addition. Compared to the Ni-based alloy cladding layers with micro-size graphite additions, the studied cladding layers exhibit improved hardness and wear resistance, good forming quality, and increased friction coefficient. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.19173


MRS Advances ◽  
2017 ◽  
Vol 2 (26) ◽  
pp. 1381-1386 ◽  
Author(s):  
Takeshi Okuno ◽  
Yasuyuki Kaneno ◽  
Takuto Yamaguchi ◽  
Takayuki Takasugi ◽  
Satoshi Semboshi ◽  
...  

ABSTRACTNi base intermetallic alloy coating was fabricated by laser cladding, controlling the laser power and powder feed rate. Atomized powder of the Ni base intermetallic alloy was laser-cladded on the substrate of stainless steel 304. The hardness and microstructure of the clad layers were investigated by Vickers hardness test, SEM, XRD and TEM observations. The hardness of the cladding layer was affected by the dilution with the substrate; it increased with decreasing laser power and increasing powder feed rate. By optimizing the dilution with the substrate, the cladding layer with an almost identical hardness level to that of the Ni base intermetallic alloy fabricated by ingot metallurgy was obtained. The TEM observations revealed that a very fine-sized microstructure composed of Ni3Al and Ni3V was partially formed even in the as-cladded state. After annealing, the two-phase microstructure composed of Ni3Al and Ni3V was developed in the cladding layer, resulting in enhanced hardness in the cladding layers fabricated in the majority of cladding conditions.


2013 ◽  
Vol 379 ◽  
pp. 145-148
Author(s):  
S.N. Namazov ◽  
E.D. Rzaev ◽  
V.F. Dzhivishov

Complex approach to studying both qualitative and quantitative friction and wear characteristics of laser-clad layers has been applied. Both type and value of wear, friction factors have been determined as depended of the coating composition, load and temperature in dry friction. Comparative analysis between laser cladding and plasma spraying has been carried out.


2016 ◽  
Vol 63 (3) ◽  
pp. 171-176 ◽  
Author(s):  
Xiaodong Zhang ◽  
Xiaohua Jie ◽  
Liuyan Zhang ◽  
Song Luo ◽  
Qiongbin Zheng

Purpose This paper aims to discuss that a WC/Co-Cr alloy coating was applied to the surface of H13 steel by laser cladding. Design/methodology/approach The oxidation behavior of the WC/Co-Cr alloy coating at 600°C was investigated by comparing it with the performance of the steel substrate to better understand the thermal stability of H13 steel. Findings The results showed that the WC/Co-Cr alloy coating exhibited better high-temperature oxidation resistance and thermal stability than did uncoated H13 steel. The coated H13 steel had a lower mass gain rate and higher microhardness than did the substrate after different oxidation times. Originality/value The WC/Co-Cr alloy coating was composed of e-Co, CW3, Co6W6C, Cr23C6 and Cr7C3; this mixture offered good thermal stability and better high-temperature oxidation resistance.


2010 ◽  
Vol 450 ◽  
pp. 214-218 ◽  
Author(s):  
Li Xia Ying ◽  
Li Dong Jiang ◽  
Fan Kai Kong ◽  
En Xia Yang

In order to improve the antiwear and antifriction performances of tribological metal surfaces for the extreme conditions, the composite coating has been fabricated on metal surfaces by the technology of laser cladding. In the experiment, Ni-based alloy, TiC and Nickel-coated graphite are used as the main ingredients of composite. The cross-sectional macrographs, microstructure, compositions, microhardness, tribological properties and the forming mechanism of the coating was tested and analyzed. Results show that laser cladding Ni60A/TiC/Nickel-coated graphite composite can obtain excellent coating with fully compact and uniform microstructure, and good interface with the substrate. The microhardness of the clad coating is over HV1000, which is five times higher than that of the steel substrate. The friction coefficient is reduced to about 0.4-0.5 in comparison with that of the steel substrate (about 0.7-0.8). At the same time, the wear resistance of the clad coating is also improved greatly.


2021 ◽  
Vol 11 (6) ◽  
pp. 2836
Author(s):  
Jae-Il Jeong ◽  
Jong-Hyoung Kim ◽  
Si-Geun Choi ◽  
Young Tae Cho ◽  
Chan-Kyu Kim ◽  
...  

The bearing is a machine element that plays an important role in rotating the shaft of a machine while supporting its weight and load. Numerous bearings have been developed to improve durability and life, depending on the functions and operating conditions in which they are desired. White metal is one of method to improve durability that is soft and bonded to the inner surface of the bearing to protect the bearing shaft. Currently, the centrifugal casting process is used as a white metal lamination method, but it involves problems such as long processing times, high defect rates and harmful health effects. In this paper, a laser cladding treatment is applied to bond powdered white metal to SCM440 alloy steel, which is used as bearing material in terms of replacing the risks of a centrifugal process. In order to understand whether laser cladding is a suitable process, this paper compares the mechanical properties of white metal produced on SCM440 alloy steel by centrifugal casting and the laser cladding process. The laser power, powder feed rate and laser head speed factors are varied to understand the mechanical properties and measure the hardness using micro Vickers and conduct field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and friction testing to understand the mechanical properties and surface characteristics. Based on the results, the hardness values of the cladding (white metal) layer ranged between 24 and 26 HV in both the centrifugal casting and laser cladding methods. However, the hardness of the white metal produced by laser cladding at about a depth of 0.1 mm rose rapidly in the cladding process, forming a heat-affected zone (HAZ) with an average hardness value of 200 HV at a laser power of 1.1 kW, 325 HV at 1.3 kW and 430 HV at 1.5 kW. The surface friction testing results revealed no significant differences in the friction coefficient between the centrifugal casting and laser cladding methods, which allows the assumption that the processing method does not significantly influence the friction coefficient.


Optik ◽  
2021 ◽  
pp. 167227
Author(s):  
Xiaoyu Shi ◽  
Daosheng Wen ◽  
Shouren Wang ◽  
Gaoqi Wang ◽  
Mingyuan Zhang ◽  
...  

Crystals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1096
Author(s):  
Qiang Shen ◽  
Yan Li ◽  
Jing Zhao ◽  
Dezheng Liu ◽  
Yongsheng Yang

In this study, a CrFeMoNbTiW high-entropy alloy (HEA) coating was prepared on a Q245R steel (American grade: SA515 Gr60) substrate by means of laser cladding. The effects of annealing temperature on the microstructure and wear resistance of the CrFeMoNbTiW coating were investigated using X-ray diffraction (XRD), a scanning electron microscope (SEM), a Vickers hardness tester and a roller friction wear tester. The results showed that the coating was mainly composed of body-centered cubic (BCC) solid solution and face-centered cubic (FCC) structural (Nb,Ti)C carbides prior to annealing, exhibiting an interdendritic structure and needlelike dendritic crystal structure with average microhardness of 682 HV0.2. The coarsening of the dendrite arms increased gradually after a 10-h long annealing treatment at 800 °C, 900 °C and 1000 °C, and a small amount of Laves phase was produced. After annealing, the highest microhardness value of the as-annealed coating reached 1176 HV0.2, which represents an increase of approximately 72.5% compared to that of the as-deposit coating. The wear resistance testing results imply that this type of coating retains good wear resistance following the annealing treatment and that its wear resistance increases in proportion to the annealing temperature in a range from 800 °C to 1000 °C.


2019 ◽  
Vol 13 (3) ◽  
pp. 5637-5652
Author(s):  
M. Zaimi ◽  
M. N. Azran ◽  
M. S. Kasim ◽  
M. R. M. Kamal ◽  
I. S. Othman ◽  
...  

Heat treatment of nickel-based alloy can increase the alloy’s hardness as well as the wear resistance properties. Nevertheless, the effect of heat treatment on the quaternary Ni alloy coating properties produced from electroless deposition bath is less known due to its composition uniqueness. In this study, Cu and Co are added in the Ni-P alloy matrix using hypophosphite-based Electroless Ni deposition method on mild steel substrate in acidic and alkaline bath. The coatings are then heat treated at 623 K for 3600s. The coatings hardness is measured using microVickers hardness tester and the surface morphology of the coatings are studied using both Scanning Electron Microscope (SEM) and X-ray diffraction (XRD) analysis. X-ray fluorescence (XRF) measurement is used to measure the coatings compositions. The wear behavior of the coatings is also investigated before and after heat treatment using ASTM G-99. The coatings from acidic-based bath produces Ni-Cu-Co-P alloy coating while the alkaline-based bath produces Ni-Co-Cu-P alloy based on XRF analysis. Results show that the hardness increases more than 20% for acidic-based bath and 40% for alkaline-based bath coating. The highest increment is the Ni-Co-Cu-P alloy, from 553.3 HV to 991.3 HV after heat treatment. The grain refinement of the coatings can be observed after heat treatment in SEM observation. This is proved by the XRD measurement results where polycrystalline Ni (111) formation is seen after heat treatment overshadowing the Cu (111) and Co (111) peaks. Ni phosphide species are also formed after the heat treatment. The polycrystalline Ni and the Ni phosphide formation, as well as the existence of Co and Cu in the alloy deposits reduces the wear rate significantly after the heat treatment.


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