A method for evaluating the crack resistance and predicting the preheating temperature of high hardness coating prepared by laser cladding

Alumina ceramic is a high performance engineering material with excellent properties, including high melting point, high hardness and brittle nature make the alumina ceramic difficult to machine and needing high cost by using conventional manufacturing methods. Coating is an important method for alumina fabrication. The excellent properties of coatings can be used for special surface protection and ceramic parts repairing. Comparing with other coating methods, laser cladding method has many good properties to overcome the drawbacks. The reported investigations on laser cladding provide little information about alumina materials for ceramic coating. In this paper, effects of different input variables of laser cladding of alumina materials for ceramic coating were studied. And this paper for the first time reported the relationship between the properties (including surface roughness, flatness and powder efficiency) and input variables such as laser power, powder feeding rate and laser head moving rate. The obtained results will be helpful to establish efficient and effective processes for ceramics coating.

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Optimization of Ni-Based WC/Co/Cr Composite Coatings Produced by Multilayer Laser Cladding

Advances in Materials Science and Engineering ◽

10.1155/2013/615464 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 13

Author(s):

Andrea Angelastro ◽

Sabina L. Campanelli ◽

Giuseppe Casalino ◽

Antonio D. Ludovico

Keyword(s):

Laser Cladding ◽

Steel Substrate ◽

Composite Coatings ◽

Metallic Matrix ◽

Optimization Procedure ◽

High Hardness ◽

Fatigue Properties ◽

Metal Composite ◽

Tungsten Carbides ◽

Cobalt Chromium

As a surface coating technique, laser cladding (LC) has been developed for improving wear, corrosion, and fatigue properties of mechanical components. The main advantage of this process is the capability of introducing hard particles such as SiC, TiC, and WC as reinforcements in the metallic matrix such as Ni-based alloy, Co-based alloy, and Fe-based alloy to form ceramic-metal composite coatings, which have very high hardness and good wear resistance. In this paper, Ni-based alloy (Colmonoy 227-F) and Tungsten Carbides/Cobalt/Chromium (WC/Co/Cr) composite coatings were fabricated by the multilayer laser cladding technique (MLC). An optimization procedure was implemented to obtain the combination of process parameters that minimizes the porosity and produces good adhesion to a stainless steel substrate. The optimization procedure was worked out with a mathematical model that was supported by an experimental analysis, which studied the shape of the clad track generated by melting coaxially fed powders with a laser. Microstructural and microhardness analysis completed the set of test performed on the coatings.

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The Effect of the Metal Phase on the Compressive and Tensile Stresses Reduction in the Superhard Nitride Coatings

Coatings ◽

10.3390/coatings10080798 ◽

2020 ◽

Vol 10 (8) ◽

pp. 798

Author(s):

Alexey O. Volkhonsky ◽

Igor V. Blinkov ◽

Dmitry S. Belov

Keyword(s):

Crack Resistance ◽

High Hardness ◽

Scratch Test ◽

Vacuum Arc ◽

Nitride Phase ◽

Tensile Stresses ◽

Compressive Stresses ◽

Cutting Inserts ◽

Evaporation Apparatus ◽

Arc Evaporation

The influence of the compressive and tensile stresses forming in the nanostructured Ti–Al–N coatings during deposition on their physical-mechanical properties was studied. The modifying influence of metal components (Ni and Cu) introduction into Ti–Al–N coatings, which do not interact with nitrogen and have limited solubility with the nitride phase, was also under research. Coatings were deposited on WC–(6 wt.%)Co carbide cutting inserts with an arc-PVD method using a cathodic vacuum arc evaporation apparatus. The introduction of Ni and Cu to the composition leads to the reduction of nitride phases grain size in both investigated coatings from 120 to 10–12 nm for Ti–Al–Cu–N and to 15–18 nm for Ti–Al–Ni–N. Thus, the hardness increases from 29 to 43 and 51 GPa for the mentioned above coatings, respectively. Meanwhile, Ti–Al–Cu–N and Ti–Al–Ni–N coatings are characterized by tensile stresses about 0.12–0.32 MPa against the much higher value of compressive stresses in Ti–Al–N coatings (4.29–5.31 GPa). The modification of Ti–Al–N coatings also leads to the changing of their destruction mechanism during the scratch-test. The critical loads characterizing the emergence of the first cracks in the coatings and complete abrasion of the coating (Lc1 and Lc3) were determined. They had the value of 20; 22 N (Lc1) and 64; 57 N (Lc3) for Ti–Al–Ni–N; Ti–Al–Cu–N coatings, respectively. The Lc1 parameter for Ti–Al–N coatings was much lower and was equal to 11 N. Along with those, Ti–Al–N coatings destructed according to the adhesion mechanism when the critical load was 35 N. In addition, the decreasing level of compressive stresses in Ti–Al–Cu–N and Ti–Al–Ni–N coatings as compared to that in the Ti–Al–N coating, their crack resistance during multi-cycle shock-dynamic impact test was significantly higher. The results can indicate that high hardness and crack resistance of the coatings is to a greater extent determined by coatings nanostructuring, not the stresses value. In addition, it confirms the possibility to obtain coatings with low stresses value while maintaining their superhardness.

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Defects in ZrO2-Reinforced Aluminum Foam Prepared by Infiltration Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.561 ◽

2011 ◽

Vol 250-253 ◽

pp. 561-564

Author(s):

Fang Wang ◽

Jian Guo Wu ◽

Lu Cai Wang

Keyword(s):

Production Process ◽

Aluminum Foam ◽

High Hardness ◽

Aluminium Foam ◽

Inhomogeneous Distribution ◽

Pouring Temperature ◽

Infiltration Process ◽

Forming Mechanism ◽

Foam Composite ◽

Preheating Temperature

The aluminium foam is reinforced by compositing ZrO2ceramic balls with high hardness. The production process includes preparing precursor using NaCl particles and ZrO2ceramic balls, infiltrating molten aluminium into precursor and cleaning NaCl particles. The defects presented during the process make the structure inhomogeneous and influence the performance of aluminium foam composite. The defects consist of inner and surface shrinkage caused by insufficient infiltration and inhomogeneous distribution of ZrO2ceramic balls in the composite. By analyzing the forming mechanism, offering right control of process and choosing correct parameters, the sound aluminium foam composite was prepared. The optimum value of pouring temperature, preheating temperature of die and particles and the suction was determined as 740°C-760°C, 480°C-500°C and -0.04Mpa, respectively. The composite has the structure with 0.8-1.2mm pore size, 60-70% porosity and ZrO2ceramic balls of 40 percent by volume. The research makes a basis for the application of the new aluminium foam composite.

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Investigation on laser cladding high-hardness nano-ceramic coating assisted by ultrasonic vibration processing

Optik ◽

10.1016/j.ijleo.2016.01.194 ◽

2016 ◽

Vol 127 (11) ◽

pp. 4596-4600 ◽

Cited By ~ 26

Author(s):

Meiyan Li ◽

Bin Han ◽

Yong Wang ◽

Lixin Song ◽

Lanyang Guo

Keyword(s):

Ultrasonic Vibration ◽

Laser Cladding ◽

Ceramic Coating ◽

High Hardness

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Effect of Cooling Modes on Microstructure and Mechanical Properties of Cr18Ni8Mo2Si Cladding to 40Cr by Laser Cladding Technology

Volume 1: Additive Manufacturing; Manufacturing Equipment and Systems; Bio and Sustainable Manufacturing ◽

10.1115/msec2019-3051 ◽

2019 ◽

Author(s):

Mingsan Xu ◽

Simo Liu ◽

Mingliang Mei ◽

Bingbing Li

Keyword(s):

Residual Stress ◽

Laser Cladding ◽

Temperature Control ◽

New Technology ◽

Scanning Speed ◽

Structural Defects ◽

Metallic Material ◽

Orthogonal Experiments ◽

Bonding Effect ◽

Preheating Temperature

Abstract Laser cladding is a new technology to clad metallic material to substrate. The objective of this research is to find optimized process parameters such as preheating temperature of substrate, laser power, scanning speed, spot diameter for cladding Cr18Ni8Mo2Si on 40Cr substrate. Moreover, effects of different cooling modes, cooling in temperature control box or natural environment were studied. Orthogonal experiments are used to find optimized parameters and better cooling strategy. Experimental results are analyzed through measurements of residual stress, micro-hardness, and metallic microstructure. It was observed that parts cooling in temperature control box show better qualities: smaller residual stress, less cracks or other structural defects, better microstructure, and better bonding effect. This research provides a guideline for further researches in temperature control of laser cladding and expands application to rotary die cutting machine.

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Hybrid Laser Deposition of Fe-Based Metallic Powder under Cryogenic Conditions

Metals ◽

10.3390/met10020190 ◽

2020 ◽

Vol 10 (2) ◽

pp. 190 ◽

Cited By ~ 5

Author(s):

Aleksander Lisiecki ◽

Dawid Ślizak

Keyword(s):

Laser Cladding ◽

Cross Sections ◽

Energy Dispersive Spectrometer ◽

High Hardness ◽

Ambient Air ◽

Laser Deposition ◽

Influence Of Process Parameters ◽

Cooling Conditions ◽

Forced Cooling ◽

Cryogenic Conditions

The purpose of this study was to demonstrate the novel technique of laser deposition of Fe-based powder under cryogenic conditions provided by a liquid nitrogen bath. Comparative clad layers were produced by conventional laser cladding at free cooling conditions in ambient air and by the developed process combining laser cladding and laser gas nitriding (hybrid) under cryogenic conditions. The influence of process parameters and cooling conditions on the geometry, microstructure, and hardness profiles of the clad layers was determined. The optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS), and XRD test methods were used to determine the microstructure and phase composition. The results indicate that the proposed technique of forced cooling the substrate in a nitrogen bath during the laser deposition of Fe-based powder is advantageous because it provides favorable geometry of the clad, low dilution, a narrow heat-affected zone, a high hardness and uniform profile on the cross-sections, homogeneity, and refinement of the microstructure. The influence of the forced cooling on microstructure refinement was quantitatively determined by measuring the secondary dendrite arm spacing (SDAS). Additionally, highly dispersed nanometric-sized (200–360 nm) precipitations of complex carbides were identified in interdendritic regions.

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Microstructural Tuning of a Laser-Cladding Layer by Means of a Mix of Commercial Inconel 625 and AISI H13 Powders

Materials ◽

10.3390/ma12030544 ◽

2019 ◽

Vol 12 (3) ◽

pp. 544 ◽

Cited By ~ 5

Author(s):

Maider Muro ◽

Josu Leunda ◽

Garikoitz Artola ◽

Carlos Soriano

Keyword(s):

Laser Cladding ◽

High Performance ◽

High Hardness ◽

Inconel 625 ◽

H13 Steel ◽

X Ray ◽

Inconel 625 Alloy ◽

Aisi H13 ◽

42Crmo4 Steel ◽

Diode Pumped

The aim of this work is to evaluate the microstructural evolutions developed by mixing a corrosion-resistant and high-performance material with a high-hardness material in a coating obtained by laser-cladding technology. In this paper, five different mixtures of Inconel 625 alloy and AISI H13 steel powders have been deposited on a plate of 42CrMo4 steel using a 2.2 kW diode pumped Nd:YAG laser. The effect of adding tool steel to a Ni-based superalloy has been analyzed by the characterization of each cladded sample using optical microscopy and scanning electron microscopy (SEM). The precipitates observed in the samples have been analyzed by energy dispersive X-ray spectroscopy (EDS X-ray). SEM micrographs and EDS analysis indicate the existence of Laves phase. It has been observed that the presence of these precipitates is stabilized in a certain range of AISI H13 addition.

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Laser Cladding of Ni60/WC/TiN Composite Coatings on 00Cr13Ni4Mo Hydro Turbine Blade Stainless Steel for Improvement of Wear Resistance

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.430-432.101 ◽

2012 ◽

Vol 430-432 ◽

pp. 101-105

Author(s):

Kai Jin Huang ◽

Hua Rui Jiang ◽

Xin Lin

Keyword(s):

Stainless Steel ◽

Wear Resistance ◽

Turbine Blade ◽

Laser Cladding ◽

Composite Coatings ◽

High Hardness ◽

Dry Sliding Wear ◽

Wear Property ◽

Hydro Turbine ◽

Wear Condition

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.

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