Dissolution Behavior of WC Reinforced Particles on Carbon Steel Surface during Laser Cladding Process

2012 ◽  
Vol 430-432 ◽  
pp. 137-141 ◽  
Author(s):  
Zhong Zhang ◽  
Hong Xi Liu ◽  
Xiao Wei Zhang ◽  
Sheng Wei Ji ◽  
Ye Hua Jiang
Keyword(s):  
Carbon Steel ◽  
Composite Coating ◽  
Laser Cladding ◽  
Laser Scanning ◽  
Energy Dispersive Spectrometer ◽  
Scanning Speed ◽  
Decomposition Reaction ◽  
Medium Carbon Steel ◽  
Dissolution Behavior ◽  
Laser Scanning Speed

Ni60WC35 self-fluxing composite coating was fabricated by transverse-flow CO2 laser apparatus on 45 medium-carbon steel surfaces. The microstructure and phase transform behavior of WC reinforced particles under the laser cladding conditions was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy-dispersive spectrometer (EDS). The results show that laser scanning speed has a great important influence on the microstructure of Ni-based WC composite coating, WC particles has a transition to the Ni-based coating. The main feature of WC particle is its edge hard phase has transformed into needle phase, and the needle phase areas increase with the decrease of the laser scanning speed. Some WC particles turn into needle clusters structure, and then white block phase. In addition, WC particle has some microscopic defects, and the surface priority defect can be dissolved. When the pool temperature rises to 1250°C, WC decomposition reaction become W2C and C. The elements diffusion can promote the dissolution of WC particles when the pool temperature rises continuously.

SYNTHESIS AND CHARACTERIZATION OF Zr-BASED AMORPHOUS AND CRYSTALLINE COMPOSITE COATING ON Ti SUBSTRATE BY LASER CLADDING

2014 ◽  
Vol 21 (01) ◽  
pp. 1450007 ◽  
Author(s):  
D. M. TANG ◽  
D. C. ZHANG ◽  
W. PENG ◽  
Z. C. LUO ◽  
X. Q. WU ◽  
...  
Keyword(s):  
Composite Coating ◽  
Amorphous Phase ◽  
Laser Cladding ◽  
Laser Scanning ◽  
Composite Coatings ◽  
Scanning Speed ◽  
Raw Material ◽  
Thin Strip ◽  
Beam Diameter ◽  
Laser Scanning Speed

A thin strip of a Zr -based alloy with a composition of Zr 60 Cu 25 Fe 5 Al 10 (in atom percent) was used as a raw material, and the composite coatings containing Zr -based amorphous phase and crystallites on Ti substrate were fabricated by a one-step laser cladding method without protection. The microstructure, phase constitution, microhardness and wear properties of the coatings were investigated. The results indicate that the microstructure of the coatings is strongly dependent on the laser scanning speed under the conditions of the laser power of 1300 W and laser beam diameter of 6 mm, and the composite coating mainly containing amorphous phase with a small amount of the crystallites can be obtained at the laser scanning speed of 10 mm/s. The composite coating exhibits much higher microhardness than the pure Ti substrate, and thus it behaves superior wear resistance in comparison with the substrate.

Dissolution Behavior of Cast WC Particles in NiCrBSi-WC Coatings by Laser Induction Hybrid Cladding

2013 ◽  
Vol 668 ◽  
pp. 283-287
Author(s):  
Sheng Feng Zhou ◽  
Xiao Qin Dai
Keyword(s):  
High Speed ◽  
Laser Scanning ◽  
Metallic Matrix ◽  
High Hardness ◽  
Scanning Speed ◽  
Eutectic Structure ◽  
Dissolution Behavior ◽  
Positive Role ◽  
Laser Scanning Speed ◽  
Laser Induction

In order to characterize the dissolution of cast WC particles in Ni-based WC coatings by laser induction hybrid rapid cladding, NiCrBSi+50 wt.% WC coatings are produced on A3 steel by low and high speed laser induction hybrid cladding (LIHC). When laser scanning speed is only 600 mm/min, the crack-free coating has pores and its dilution is as high as 45%. At the bottom of coating, the cast WC particles are dissolved completely and the herringbone M6C eutectics are precipitated. In the center of coating, the cast WC particles are also dissolved completely and the acicular, blocky and dendritic carbides with relatively low hardness are precipitated. At two sides of coating, some cast WC particles are dissolved partially and interact with Ni-based alloy to form an alloyed reaction layer, while others preserve the primary eutectic structure and high hardness. When laser scanning speed and powder feeding rate are increased to 1500 mm/min and 85.6 g/min, the coating has cracks but no pores. Its dilution can be markedly decreased to 7.8%. Moreover, a majority of WC particles are still composed of primary eutectic structure and keep their high hardness, which can play a positive role in strengthening Ni-based metallic matrix.

Influence of Scanning Speed on Microstructure and Hardness during Laser Cladding High-Cr Cast Iron

2013 ◽  
Vol 395-396 ◽  
pp. 1127-1131 ◽  
Author(s):  
Wei Zhang
Keyword(s):  
Cast Iron ◽  
Laser Cladding ◽  
Laser Scanning ◽  
Scanning Speed ◽  
Fish Bone ◽  
Cladding Layer ◽  
Metallurgical Bonding ◽  
Laser Scanning Speed ◽  
Gas Cavity ◽  
Cladding Layers

The experiments of laser cladding on the surface of 20 steel were made. High-chromium (Cr) cast iron powder was used as cladding material. The microstructure and hardness of laser cladding layers under different scanning speed were studied. The experiments showed that high-Cr cast iron cladding layer had better properties such as minute crystals, high density, no crack, no gas cavity and good metallurgical bonding with base metal. When the scanning speed was low, such as 10mm/min, the microstructure of cladding layer was cellular dendrite. There were much carbide with the shape of fish-bone distributing among cellular grains. Under higher scanning speed (from 100mm/min to 300mm/min), needle-shaped primary cementite would come into being. When laser scanning speed was 500mm/min, the carbide of cladding zone was very thin. With the increasing of laser scanning speed, the average hardness of cladding zone increased from 388HV0.2 to 580 HV0.2.

Effect of laser scanning speed on microstructure and wear properties of T15M cladding coating fabricated by laser cladding technology

2018 ◽  
Vol 110 ◽  
pp. 163-171 ◽  
Author(s):  
Xiangyi Jiao ◽  
Jun Wang ◽  
Canming Wang ◽  
Zhengqi Gong ◽  
Xinxing Pang ◽  
...  
Keyword(s):  
Laser Cladding ◽  
Laser Scanning ◽  
Scanning Speed ◽  
Wear Properties ◽  
Laser Scanning Speed

scholarly journals The Effect of Laser Scanning Speed on Microstructure and Performance of Cr3C2-NiCr Cermet Fabricated by in-situ Laser Cladding

2021 ◽  
pp. X
Author(s):  
Deyuan LOU ◽  
Shaokun YANG ◽  
Sheng MEI ◽  
Qing LIU ◽  
Jian CHENG ◽  
...  
Keyword(s):  
Laser Cladding ◽  
Laser Scanning ◽  
Scanning Speed ◽  
Powder Mixtures ◽  
Laser Scanning Speed ◽  
Nickel Based Alloy ◽  
And Performance ◽  
Microstructure And Performance ◽  
Carbide Content

To explore the effect of laser scanning speed on the microstructure and performance of Cr3C2-NiCr cermet layers fabricated by in-situ laser cladding, Cr3C2-NiCr cermet layers were laser cladded from Ni/Cr/Graphite (25:65:10 wt.%) elemental powder mixtures. The microstructures of the laser cladded cermet layers and the formation mechanism were investigated. In addition, the effect of laser scanning speed on the microstructure, friction and corrosion performance of the Cr3C2-NiCr cermet layers was studied. The results indicated that the in-situ laser cladded Cr3C2-NiCr cermet layers were composed of NiCr binder and Cr3C2. The laser scanning speed had a significant influence on the carbide content, composition and size. Furthermore, it affected the in-situ laser cladded cermet layer’s hardness and wear resistance. The corrosion resistance of the in-situ laser cladded cermet layer was superior to that of laser cladded nickel-based alloy and was improved with decreasing laser scanning speed.

scholarly journals Investigation on Microstructure, Hardness, and Corrosion Resistance of Mo–Ni–B Coatings Prepared by Laser Cladding Technique

Coatings ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 856 ◽  
Author(s):  
Xiaojie Ni ◽  
Shengze Wang ◽  
Yuantao Zhao ◽  
Wenge Li ◽  
Xiong Jiao
Keyword(s):  
Corrosion Resistance ◽  
Laser Cladding ◽  
Laser Scanning ◽  
Bottom Layer ◽  
Scanning Speed ◽  
Corrosion Current ◽  
Corrosion Resistant ◽  
Cermet Coatings ◽  
Laser Scanning Speed ◽  
Corrosion Resistant Coatings

The hard and corrosion resistant coatings of Mo2NiB2 cermet were prepared by the laser cladding technique. The influences of the Mo:B ratio and the laser scanning speed on the microstructure and property of the Mo2NiB2 cermet coatings were investigated. The results showed that the laser scanning speed of 1.5 mm/s and the Mo:B ratio of 1 were more beneficial to the formation of Mo2NiB2 cermet than 2.0 mm/s and 0.8, 1.2, respectively. The amount of the Mo2NiB2 ceramic phases were decreased from the top layer to the bottom layer of the coating. The changes of microstructure and composition led to the changes of hardness and corrosion resistance of the Mo2NiB2 cermet coatings. The coating prepared at the Mo:B ratio of 1 and the scanning speed of 1.5 mm/s possessed the highest hardness, and the hardness gradually decreased from the top layer to the bottom layer of the coating. The formation of Mo2NiB2 and {FeM} phases led to the enhanced corrosion resistance of the Mo2NiB2 cermet coatings, and the coating prepared at the Mo:B ratio of 0.8 possessed the best corrosion resistance and the minimum corrosion current.

Laser Cladding In Situ Tungsten Carbide Reinforced Ferrous Matrix Surface Composites

2011 ◽  
Vol 189-193 ◽  
pp. 771-776 ◽  
Author(s):  
Ying Ying Chen ◽  
Wen Ge Li
Keyword(s):  
Tungsten Carbide ◽  
Laser Cladding ◽  
Laser Power ◽  
Laser Scanning ◽  
Synthesis Method ◽  
Scanning Speed ◽  
Hardness Measurement ◽  
Element Distribution ◽  
Matrix Surface ◽  
Laser Scanning Speed

Tungsten carbide cermets coating on carbon steel were fabricated by laser clad cooperation combustion synthesis method. The microstructure, phase, element distribution and microhardness have been analyzed with the aid of SEM, XRD, EDS, EPMA and microhardness-tester. It is shown that the coating consisted of WC, CW3, W2C, WCx, and FeNi3. The results of hardness measurement showed that the hardness was superior to substrate. Analyze the effect of different laser power and different laser scanning speed on the quality of the laser cladding surface, the surface quality gets better with the increasing of the laser power, and gets better with the reducing of the scanning speed.

A STUDY ON SCAN SPEED RELATIONSHIP WITH MICROSTRUCTURAL EVOLUTION, PHASE COMPOSITION AND MICROHARDNESS OF Ni-CONTAINING INTERMETALLIC COATINGS ON Ti–6Al–4V USING LASER CLADDING TECHNIQUE

2018 ◽  
Vol 25 (08) ◽  
pp. 1950035 ◽  
Author(s):  
O. S. ADESINA ◽  
A. P. I. POPOOLA ◽  
S. L. PITYANA ◽  
D. T. OLORUNTOBA
Keyword(s):  
Laser Cladding ◽  
Laser Scanning ◽  
Gas Flow ◽  
Microstructural Analysis ◽  
Scanning Speed ◽  
Metallurgical Bonding ◽  
Clad Layer ◽  
Fine Microstructure ◽  
Scan Speed ◽  
Laser Scanning Speed

Titanium alloys have been used for variety of engineering applications but their relatively low hardness and low thermal conductivity are shortcomings that have reduced their potential use. In this work, attempts have been made to study the effects of laser scanning speed and admixed fraction of reinforced Ni–Co powders on clad layer formation and its corresponding properties on Ti–6Al–4V. Laser power of 750[Formula: see text]W, beam size of 3[Formula: see text]mm with argon shield gas flow rate of 1.2[Formula: see text]L/min was made constant, while the powders were premixed and deposited on Ti–6Al–4V with varying compositions at different scanning speeds of 0.6 and 1.2[Formula: see text]m/min. The microstructural analysis, phase constituents and hardness properties of Ni–Co intermetallics reinforced clads were also examined. The morphology of the resultant coatings was analyzed using X-ray diffractometry (XRD) and scanning electron microscopy (SEM) equipped with energy dispersive spectrometry (EDS). The research results showed that laser cladding coatings displayed enhanced properties such as fine microstructure and good metallurgical bonding with the substrate containing minimal pores with respect to the substrate. Furthermore, the microstructure revealed the formation of various fractions of interdendritic compounds/intermetallics dispersed within the coating matrix which could be responsible for the increased hardness obtained. The average hardness of the coating was about 856[Formula: see text]HV [Formula: see text], which was about 2.5 times that of the substrate.

Investigation on the Process Characteristics of Laser Cladding Fabrication Using 45 Carbon Steel Wire

2012 ◽  
Vol 499 ◽  
pp. 147-151
Author(s):  
Jin Sun ◽  
Singare Sekou
Keyword(s):  
Carbon Steel ◽  
Laser Cladding ◽  
Nd:Yag Laser ◽  
Laser Scanning ◽  
Steel Wire ◽  
Scanning Speed ◽  
Deposition Process ◽  
Process Characteristics ◽  
Wire Feeding ◽  
Metal Microstructure

This study investigates the effect of wire feeding direction, angle, wire feeding speed, laser scanning speed and laser power in a high power Nd:YAG laser direct metal deposition process for single and multilayered clad/parts. The lap cladding experiment using 500 W Nd:YAG laser is designed to study the best lap rate of 45 carbon steel. The microstructure and micro hardness of the melting track shows that dense metal microstructure can be obtained using laser cladding.

scholarly journals Temperature Field Numerical Analysis Mode and Verification of Quenching Heat Treatment Using Carbon Steel in Rotating Laser Scanning

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 534 ◽  
Author(s):  
Tsung-Pin Hung ◽  
Chao-Ming Hsu ◽  
Hsiu-An Tsai ◽  
Shuo-Ching Chen ◽  
Zong-Rong Liu
Keyword(s):  
Temperature Field ◽  
Carbon Steel ◽  
Laser Scanning ◽  
Steel Specimen ◽  
Scanning Speed ◽  
Element Model ◽  
Medium Carbon Steel ◽  
Temperature History ◽  
Circular Path ◽  
Processing Efficiency

Temperature history and hardening depth are experimentally characterized in the rotational laser hardening process for an AISI 1045 medium carbon steel specimen. A three-dimensional finite element model is proposed to predict the temperature field distribution and hardening zone area. The laser temperature field is set up for an average distribution and scanned along a circular path. Linear motion also takes place alongside rotation. The prediction of hardening area can be increased by increasing the rotational radius, which in turn raises the processing efficiency. A good agreement is found between the experimental characterized hardness value and metallographic composition. The uniformity of the hardening area decreases with increasing laser scanning speed. The increased laser power input could help to expand the hardening depth.

Sign in / Sign up

Export Citation Format

Share Document