Microstructure and abrasive wear behavior of a novel FeCrMoVC laser
cladding alloy for high-performance tool steels
高性能工具钢 FeCrMoVC激光熔覆合金的微观结构及磨料磨损性能
Wear, Volumes 382–383, 15 July 2017, Pages 107-112
J. Zeisig, N. Schädlich, L. Giebeler, J. Sander, J. Hufenbach
摘要：This work shows the successful application of a novel
Fe85Cr4Mo8V2C1 (wt%) laser cladding wire material on a high-performance tool
steel (1.2379, X155CrMo12-1) using a pulsed Nd:YAG laser system. Due to the high
cooling rates during the welding process and appropriate laser parameters, a
fine, homogeneous microstructure composed of martensite, austenite as well as
VC- and Mo2C-type carbides was formed. This combination of phases along with
their special morphology and distribution result in crack-free dense coatings
with an enhanced hardness and abrasive wear resistance compared to the substrate
material and a conventionally applied cladding alloy. In summary, laser cladding
with the novel FeCrMoVC alloy shows a high potential for repair welding and
hardfacing of high-performance carbon-rich steel tools.
On the formation features, microstructure and microhardness of single
laser tracks formed by laser cladding of a NiCrBSi self-fluxing alloy
NiCrBSi自熔性合金激光熔覆单道的形成特征、微观结构及微小硬度
Optics and Lasers in Engineering, Volume 106, July 2018, Pages 32-38
O. G. Devojno, E. Feldshtein, M. A. Kardapolava, N. I. Lutsko
摘要：In the present paper, the influence of laser cladding conditions on
the powder flow conditions, as well as the microstructure, phases and
microhardness of an Ni-based self-fluxing alloy coating are described. The
optimal granulations of a self-fluxing alloy powder and the relationship between
the flow of powder of various fractions and the flow rate and pressure of the
transporting gas have been determined. The laser beam speed, track pitch and the
distance from the nozzle to the coated surface influence the height and width of
single tracks. Regularities in the formation of microstructure under different
cladding conditions are defined, as well as regularity of distribution of
elements over the track depth and in the transient zone. The patterns of
microhardness distribution over the track depth for different cladding
conditions are found. These patterns as well as the optimal laser spot pitch
allowed obtaining a uniform cladding layer.
High temperature wear performance of laser-cladded FeNiCoAlCu high-entropy
alloy coating
激光熔覆FeNiCoAlCu高熵合金涂层的高温耐磨性能
Applied Surface Science, Volume 445, 1 July 2018, Pages 113-122
Guo Jin, Zhaobing Cai, Yajie Guan, Xiufang Cui, Dan zhang
摘要：High temperature wear is a common phenomenon, but in the field of
high-entropy alloys, there are limited literatures on the wear behavior of
laser-cladded high-entropy alloy coatings at elevated temperature. In this work,
the wear performance of laser-cladded FeNiCoAlCu high-entropy alloy coating at
room temperature, 200 °C, 400 °C, 600 °C and 800 °C were investigated in detail.
The phase constitution and microstructure of laser-cladded FeNiCoAlCu
high-entropy alloy coating were analyzed by XRD, SEM, EPMA and TEM. The results
show that the synthesized FeNiCoAlCu high-entropy alloy coating is composed of
FCC and BCC solid solution phases with a typical uniform dendrite
microstructure, and the phase constitution of inter-dendritic region and
dendritic region are Fe-rich BCC and Cu-rich FCC solid solution, respectively.
The high-temperature XRD and DSC results indicate that the laser-cladded
FeNiCoAlCu high-entropy alloy coating has a good thermal-stability below 780 °C.
The laser-cladded FeNiCoAlCu high-entropy alloy coating also has a good wear
performance at high temperature, which is mainly attributed to the formation of
oxide films on the surface of the coating. The wear mechanisms are dominated by
abrasive wear and oxidative wear.
Microstructure and wear resistance of laser cladded composite coatings
prepared from pre-alloyed WC-NiCrMo powder with different laser spots
基于不同激光光斑的预合金WC-NiCrMo粉末激光熔覆复合涂层的微观结构与耐磨性
Optics & Laser Technology, Volume 101, May 2018, Pages 520-530
Jianhua Yao, Jie Zhang, Guolong Wu, Liang Wang, Rong Liu
摘要：The distribution of WC particles in laser cladded composite
coatings can significantly affect the wear resistance of the coatings under
aggressive environments. In this study, pre-alloyed WC-NiCrMo powder is
deposited on SS316L via laser cladding with circular spot and wide-band spot,
respectively. The microstructure and WC distribution of the coatings are
investigated with optical microscope (OM), scanning electron microscopy (SEM),
energy dispersive spectrometer (EDS), and X-ray diffraction (XRD). The wear
behavior of the coatings is investigated under dry sliding-wear test. The
experimental results show that the partially dissolved WC particles are
uniformly distributed in both coatings produced with circular spot and wide-band
spot, respectively, and the microstructures consist of WC and M23C6 carbides and
γ-(Ni, Fe) solid solution matrix. However, due to Fe dilution, the two coatings
have different microstructural characteristics, resulting in different hardness
and wear resistance. The wide-band spot laser prepared coating shows better
performance than the circular spot laser prepared coating.
Study on the effect of Cu addition on the microstructure and properties of
NiTi alloy fabricated by laser cladding
铜添加对激光熔覆NiTi合金微观结构和性能的影响
Materials Letters, Volume 220, 1 June 2018, Pages 148-151
Bo Fu, Kai Feng, Zhuguo Li
摘要：Microstructure and properties of laser cladded NiTi and NiTiCu
coatings were investigated to reveal the effect of Cu addition in this system.
The XRD and SEM results indicated that Cu addition formed a ternary phase
TiNi0.8Cu0.2, distributed in the grain boundary region of the matrix. The
microhardness of NiTiCu coating was much higher than that of NiTi coating,
reaching 600–700 HV. The wear resistance was improved with the friction
coefficient decreased by 25.8% and the wear loss decreased by almost 50%. This
was due to the grain boundary strengthening and wetting effect caused by the
intergranular ternary phase and the change of the phase transformation
behavior.
Research and development status of laser cladding on magnesium alloys: A
review
镁合金表面激光熔覆技术的研究与发展现状综述
Optics and Lasers in Engineering, Volume 93, June 2017, Pages 195-210
Jianli Liu, Huijun Yu, Chuanzhong Chen, Fei Weng, Jingjie Dai
摘要：Magnesium alloys are one of the most promising lightweight
structural materials. However, the poor corrosion and wear resistance restrain
their further application. As a kind of surface modification technique, laser
cladding treatment is superior to others owing to its unique characteristics
such as high efficiency and the metallurgical bonding between the coatings and
substrates. In this paper, the laser cladding process and the effects of
processing parameters, including laser power, scanning velocity, beam focal
position, feeding ways of the material etc., are discussed in detail. The
material systems preplaced on magnesium alloys are summarized. Except for the
traditional metallic materials, novel ternary alloys, amorphous alloys and high
entropy alloys (HEAs) are widely used and apparent advantages are exhibited. In
terms of the problems existing in the laser cladding process of magnesium
alloys, some potential solutions and the development tendency are reviewed.
