scholarly journals Laser Cladding of Ni-Co-W Composite Coating on Stainless Steel to Enhance Wear Resistance

2021 ◽  
Author(s):  
Linlin ZHANG ◽  
Dawei ZHANG

Ni-Co-W composite coatings modified by different contents of Co-based alloy powder in the Ni-based alloy with 35 wt.% WC (Ni35WC) were deposited on stainless steel by laser cladding. The influence of compositional and microstructural modification on the wear properties has been comparatively investigated by XRD, SEM, and EDS techniques. It was found that the austenite dendrites in the modified coating adding 50 wt.% Co-based alloy were refined and a lot of Cr23C6 or M23(C, B)6 compounds with fine lamellar feature were formed around austenitic grain boundaries or in the intergranular regions. The contribution of element Co to the modification of Ni35WC coating is that it cannot only promote the formation of more hard compounds to refine austenite grains, but also refine the size of precipitates, and change the phase type of eutectic structure as a result of disappeared Cr boride brittle phases. A noticeable improvement in wear resistance is obtained in the Ni35WC coating with 50 wt.% Co-based alloy, which makes the wear rate decreased by about 53 % and 30% by comparison to that of the substrate and the Ni35WC coating, respectively. It is suggested that the improvement is closely related to the composite coating being strengthened owing to the increase of coating hardness, formation of a fine-grained microstructure caused by Co, and fine hard precipitate phases in the eutectic structure.

2012 ◽  
Vol 19 (05) ◽  
pp. 1250052 ◽  
Author(s):  
X. H. WANG ◽  
M. ZHANG ◽  
B. S. DU ◽  
S. LI

Iron-based composite coatings reinforced with TiB2–TiC multiple ceramic have been fabricated from a precursor of B4C , TiO2 and Al powders by laser cladding. The effect of TiO2 and Al on the microstructure and wear properties of the coatings was investigated. The results showed that the volume fraction, type and size of the reinforcements were influenced by the content of TiO2 and Al . TiB2 and TiC were evenly distributed in the coating; however, most of Al2O3 were ejected from the coatings, only few of them retained in the coating acting as nucleation core of reinforcement or inclusion. The microhardness and wear resistance of the coatings were improved, whereas the friction coefficients of the coatings were considerably lower than that of substrate.


2013 ◽  
Vol 433-435 ◽  
pp. 2054-2057
Author(s):  
Peng Xu ◽  
Cheng Xin Lin ◽  
Xin Peng Yi ◽  
Chao Yu Zhou

AISI 304 stainless steel powder and Al2O3 powder was used to produce laser cladding composite coatings in order to improve the surface wear resistance of 45 steel. Microstructure of the composite coating was examined and analyzed by metallographic microscope. Microhardness and wear resistance of the composite under different scanning velocities were evaluated. The results show that the composite coating is composed of planar crystal, cellular crystal, dendritic crystal and fine equiaxed; the composite coatings under different technological parameters are made of the same phases, ferrite (α) and austenite (γ) phases. Microhardness of the composite is enhanced along with the increase of scanning velocity; effect of scanning velocity on wear loss of the composite coatings is not significant.


2012 ◽  
Vol 430-432 ◽  
pp. 101-105
Author(s):  
Kai Jin Huang ◽  
Hua Rui Jiang ◽  
Xin Lin

To improve the wear property of 00Cr13Ni4Mo hydro turbine blade stainless steel, Ni-based composite coatings were fabricated on 00Cr13Ni4Mo stainless steel by laser cladding using mixed powders of Ni60, WC and TiN. The microstructure of the coatings was characterized by XRD and SEM techniques. The wear resistance of the coatings was evaluated under dry sliding wear condition at room temperature. The results show that the coatings mainly consist of Ni-based solid solution, WC and TiN phases. The coatings exhibit excellent wear resistance due to its high hardness of WC and TiN phases. The main wear mechanisms of the coatings and the 00Cr13Ni4Mo sample are different, the former is abrasive wear and the latter is adhesive wear.


2012 ◽  
Vol 19 (02) ◽  
pp. 1250009 ◽  
Author(s):  
PENG LIU ◽  
WEI GUO ◽  
DAKUI HU ◽  
HUI LUO ◽  
YUANBIN ZHANG

The synthesis of hard composite coating on titanium alloy by laser cladding of Al/Fe/Ni+C/Si3N4 pre-placed powders has been investigated in detail. SEM result indicated that a composite coating with metallurgical joint to the substrate was formed. XRD result indicated that the composite coating mainly consisted of γ- (Fe, Ni) , FeAl , Ti3Al , TiC , TiNi , TiC0.3N0.7 , Ti2N , SiC , Ti5Si3 and TiNi . Compared with Ti-3Al-2V substrate, an improvement of the micro-hardness and the wear resistance was observed for this composite coating.


2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Zhenglei Yu ◽  
Lunxiang Li ◽  
Deqiang Zhang ◽  
Guangfeng Shi ◽  
Guang Yang ◽  
...  

AbstractNickel-based alloy coatings were widely used for the remanufacturing of dies and moulds by laser cladding, but the crack sensitivity would be increase due to the higher strength and hardness, which reduced the wear resistance of Ni-based alloys. In this paper, Ni-based coatings with the addition of a plastic phase (an austenitic stainless net) were prepared using laser cladding technology, and the CeO2 was added in cladding layers. The cracking mechanism, microhardness, microstructure, phase composition, and wear properties were investigated. The relationship between thermal stress and the elastic and plastic fracture had been developed from the standpoint of fracture mechanics and thermal elastic fracture mechanics. The fracture criterion of the nickel-based coating was obtained, and the study has shown that the crack sensitivity could be reduced by decreasing the thermal expansion coefficient Δα. Thus, a new method was proposed, which the stainless steel nets were prefabricated on the substrate. It was found that the number of cracks reduced significantly with the addition of stainless steel net. When the stainless steel net with 14 mesh was added in Ni-based coatings, the average microhardness of nickel composite coating was 565 HV0.2, which was 2.6 times higher than that of the 45 steel substrate. Although the rare earth oxide 4 wt.% CeO2 and stainless steel net were added in the Ni-based coating reducing the microhardness (the average microhardness is 425 HV0.2), the wear resistance of it improved substantially. The wear volume of Ni-based composite coating was 0.56×10−5 mm3·N−1·m−1, which was 85.1% lower than that of 45 steel. The experiment results have shown that the Nickel-based composite coating is equipped with low crack sensitivity and high abrasive resistance with austenitic stainless net and the rare earth oxide 4 wt.% CeO2. This research offers an efficient solution to produce components with low crack susceptibility and high wear-resistance coatings fabricated by laser cladding.


Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 300 ◽  
Author(s):  
Haijiang Wang ◽  
Wei Zhang ◽  
Yingbo Peng ◽  
Mingyang Zhang ◽  
Shuyu Liu ◽  
...  

FeCoCrNi-Mo high entropy alloy/diamond composite coatings were successfully prepared by high speed laser cladding. A high scanning speed was adopted (>30 mm/s), and the effects of laser power, scanning speed, and diamond content on the microstructure and wear resistance of the composite coating were studied. The processing parameters of laser cladding had significant influence on the dilution ratio, graphitization of diamond, and wear resistance of the composite coatings. When the laser cladding parameters were 3000 W of laser power and the high scanning speed of 50 mm/s, the composite coating exhibited a uniform microstructure, the lowest dilution ratio, and the best wear resistance. The wear resistance of the composite coating was enhanced with the addition of diamond, but microcracks also increased. When the amount of diamond was 15 wt.%, the best combination of microstructures and wear resistance was obtained.


2010 ◽  
Vol 97-101 ◽  
pp. 1510-1513
Author(s):  
Jun Zhou ◽  
Fa Qin Xie ◽  
Yong Quan Li ◽  
Xiang Qing Wu

Co-based composite coatings reinforced by TiN particles were fabricated on Ni-based superalloy substrate by using a 5 kW CO2 laser. The microstructures and phases constitution of the composite coating were studied by means of optical microscope (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The microhardness and wear resistance of the coating were also examined. The results showed that the composite coating was mainly composed of γ-Co, TiN, TiC, (Cr, W)23C6 and Co3Ti. And different solidification morphologies, such as planar, cellular and dendrite, were obtained. Structural transformations were attributed to the temperature gradient and solidification rate in metal-melting region. It was found that the microhardness of the composite coating was enhanced prominently as compared to the substrate region, which should be due to the undissolved TiN and other new complicated phase. Friction and wear tests without lubrication showed that the addition of TiN particles into Co-based coating can improve its wear resistance significantly without evidently increasing the friction coefficient of coating.


2020 ◽  
pp. 2050050
Author(s):  
S. BUYTOZ ◽  
M. KOK ◽  
I. N. QADER ◽  
E. BALCI ◽  
F. DAGDELEN

It is aimed to investigate the coating of AISI316 stainless steel with NiCrBSi/WC at different ratios using TIG method. In this study, the Ni-based WC-reinforced MMC layer was manufactured by the TIG composite coating method, and then the microstructure of the coating layer was examined. Microstructure and phase components of the composite coatings were characterized by optical microscopy, scanning electron microscopy, and X-ray diffraction. A metallurgic bound was found between the coating layer and the substrate through the TIG coating process. WC was re-solidified in the matrix by dissolving with high input energy. Several phases were found, including Ni-rich ([Formula: see text]-Ni) primary dendritic phase, Ni-Ni3B, and Ni3Si eutectic structure, Cr7C3, Cr2B3, Cr3Ni2, Ni2W4C, and Ni[Formula: see text]W3 phases in dendritic structures. The presence of carbides in the structure had affected the hardness of the coating. The maximum hardness value was found to be 469.5 HV and the hardness of the coating layers was increased at least 2.5 times compared to that of the substrate material.


2020 ◽  
Vol 27 (10) ◽  
pp. 1950219
Author(s):  
ZHIYUAN LIU ◽  
GUANCHAO LI ◽  
JIANING LI ◽  
MENGZHEN WANG ◽  
HUIJUN YU ◽  
...  

The amorphous phase (AP) and nanocrystalline particle (NP)-reinforced composite coating was fabricated by laser cladding (LC) of the Ni45-WC mixed powders on the 304 stainless steel. An LC technique favored APs as well as NPs to be formed due to their rapid cooling and solidification characteristics, so the wear resistance of the Ni-base coating was improved. Microstructures and wear resistance of the fabricated composite coating were studied extensively. The test results showed that the microhardness and wear resistance of this LC coating were enhanced under the actions of NPs, APs and the ceramics. The study of the laser synthesis of NPs provided a theoretical basis for improving the LC technique.


Coatings ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 684 ◽  
Author(s):  
Jianfeng Li ◽  
Zhencai Zhu ◽  
Yuxing Peng ◽  
Gang Shen

In this study, the effect of carbon fibers (CFs) on the microstructure and wear resistance of Fe-based alloy coating produced by laser cladding was investigated by X-ray diffractometer (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS), and wear tester. The results indicated that with the addition of CFs, the microstructure of the composite coating mainly transformed from α-Fe cellular dendrites and γ-Fe/(Cr, Fe)7C3/CrB eutectics to bulk-like (Cr, Fe)7C3, nano-size B4C, and γ-(Fe, Ni)/(Cr, Fe)23C6 lamellar eutectics. Additionally, the microhardness and wear resistance of the composite coating compared with the original coating both increased by approximately two times. The original coating showed the dominant wear mechanisms of micro-cutting and serious brittle spalling, while the composite coating with CFs showed the main wear mechanism of slight scratching.


Sign in / Sign up

Export Citation Format

Share Document