scholarly journals Crack Restraining Methods and their Effects on the Microstructures and Properties of Laser Cladded WC/Fe Coatings

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2541 ◽  
Author(s):  
Qiu-Lian Dai ◽  
Can-bin Luo ◽  
Fang-yi You
Keyword(s):  
Wear Resistance ◽  
Laser Cladding ◽  
Low Cost ◽  
Annealing Treatment ◽  
Melting Process ◽  
Laser Cladding Process ◽  
Process Heat ◽  
Crack Susceptibility ◽  
Better Than

Laser cladded WC/Fe coatings have the advantages of low cost and high abrasion wear resistance. However, cracks always appear in WC/Fe coatings, which limits their industrial application. In this paper, the co-effects of the re-melting process, heat treatments, and amount of Co element on the cracking susceptibility, microstructures, and mechanical properties of WC/Fe laser cladding coatings were studied. Experimental results show that re-melting process is helpful to improve the surface quality of the coating and to reduce the cracking susceptibility. The hardness of the coating decreases slightly but distributes more uniformly. Cracks in the coating can be inhibited effectively by preheating the substrate to 250 °C and maintaining the temperature during the laser cladding process, as well as applying an annealing treatment at 300 °C for 1 h. Heat treatment also results in a slight decrease in the hardness. Crack initiation cannot be restrained completely by applying the above two methods when laser cladding a big area of coating. On the basis of the above two methods, addition of Co element to the coating can further improve its toughness and decrease the crack susceptibility. Crack-free WC/Fe coating can be manufactured when 8% Co is added, and its wear resistance is much better than that of the hardened medium steel, especially when the wear time is long.

Microstructure and Grain Abrasion Properties of Cr3C2-NiCr Coating Prepared by Laser Cladding Method

2012 ◽  
Vol 271-272 ◽  
pp. 3-7
Author(s):  
Long Wei ◽  
Zong De Liu ◽  
Xin Zhi Li ◽  
Ming Ming Yuan ◽  
Cheng Yuan Zhong
Keyword(s):  
Wear Resistance ◽  
Wear Rate ◽  
Laser Cladding ◽  
Micro Hardness ◽  
High Quality ◽  
Wear Resistant ◽  
Hardness Tester ◽  
Technology Analysis ◽  
Main Component

Cr3C2-NiCr has high quality of wear resistant properties and is widely used in abrasive environment. In this paper, Cr3C2-NiCr coating was prepared on 45 steel by laser cladding technology. Analysis and research of the coatings were achieved by SEM and XRD to determine the main component and the different region on coatings. The hardness and the element component were investigated by micro-hardness tester and EDS. Abrasion tests were performed to contrast the wear resistance of two materials. The results indicate that the hardness of the coatings is nearly 3 times as the substrate. The coatings are well combined with the substrate and the phase of Cr3C2 has a large proportion in the coatings. Abrasion tests show that the average of wear rate on substrate is 5.2 times as the coatings.

Wear Resistance of Laser Cladded NiCrFeSiB Self-Fluxing Composite Coatings

2016 ◽  
Vol 254 ◽  
pp. 290-295
Author(s):  
Iosif Hulka ◽  
Ion Dragoş Uţu ◽  
Viorel Aurel Şerban ◽  
Alexandru Pascu ◽  
Ionut Claudiu Roată
Keyword(s):  
Wear Resistance ◽  
Laser Cladding ◽  
Wear Behavior ◽  
Protective Coatings ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Base Material ◽  
Laser Cladding Process ◽  
Metallurgical Bond ◽  
Feedstock Material

Laser cladding process is used to obtain protective coatings using as heat source a laser. This melts the substrate and the feedstock material to create a protective coating and provides a strong metallurgical bond with minimal dilution of the base material and reduced heat affected zone. In the present study a commercial NiCrSiFeB composition was deposited by laser cladding process using different parameters onto the surface of a steel substrate. The obtained coatings were investigated in terms of microstructure, hardness and wear behavior. The experimental results revealed that the laser power had a considerable influence on the wear resistance of NiCrSiFeB coatings.

scholarly journals Investigation on Nano-Self-Lubricant Coating Synthesized by Laser Cladding and Ion Sulfurization

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Meiyan Li ◽  
Bin Han ◽  
Conghua Qi ◽  
Yong Wang ◽  
Lixin Song
Keyword(s):  
Wear Resistance ◽  
Composite Coating ◽  
Laser Cladding ◽  
Dendritic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Atomic Force ◽  
Valence States ◽  
Microstructure Morphology ◽  
Better Than

The composite processing between laser cladding and low temperature (300°C) ion sulfurization was applied to prepare wear resistant and self-lubricating coating. The microstructure, morphology, phase composition, valence states, and wear resistance of the composite coating were investigated by scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS), and friction and wear apparatus. The results indicate that the laser cladding Ni-based coatings and the maximum hardness of 46.5 HRC were obtained when the percent of pure W powder was 10%, composed of columnar dendrites crystals and ultrafine dendritic structure. After ion sulfurization at 300°C for 4 h, the loose and porous composite coating is formed with nanograins and the granularity of all grains is less than 100 nm, which consists ofγ-(Fe, Ni), M23C6carbides, FeS, FeS2, and WS2. Furthermore, the wear resistance of the composite coating is better than the laser cladding Ni55 + 10%W coating, and the friction coefficient and mass losses under the conditions of dry and oil lubrication are lower than those of laser cladding Ni55 + 10%W coating.

scholarly journals Quality of Dried Anchovy (Stolephorus sp.) from Buru Island Produced by Using Closed Sun Dryer

2018 ◽  
Vol 21 (3) ◽  
pp. 543
Author(s):  
Imelda Krisanta Enda Savitri ◽  
Bernita Silaban ◽  
R.B.D. Sormin
Keyword(s):  
Traditional Method ◽  
Low Cost ◽  
National Standard ◽  
Plate Count ◽  
Drying Method ◽  
Vibrio Cholera ◽  
E Coli ◽  
Total Plate Count ◽  
Better Than

Anchovies drying method in Saliong, Batuboi village, Kayeli Bay has been done by spreading fish on the ground covered by mat or net due to low cost and easy to apply. However, there are no guarantee in the sanitation and hygienic. The objective of this research was to study the effect of closed sun drying method on the quality of dried anchovies (Stolephorus sp). The method was using closed cabinet sun dryer prototype covered by transparence plastic multi racks. Parameters observed involve: organoleptic, moisture content, acid insoluble, total plate count (TPC), E. coli, Salmonella sp., Vibrio cholera and fungi according to Indonesian national standard reference (SNI). The result showed the dried anchovy have an organoleptic grade refers to appearance, smells and texture were 8.40, 8.33 and 8.27 respectively. Moreover, moisture 17.50%; acid insoluble ash 0.32%; total bacterial (TPC) 6.92x102; E. coli, Salmonella sp., V. cholera and fungi were negative. For comparison, dried anchovy produced by using conventional/traditional drying had an organoleptic grade refers to appearance, smells and texture were 7.67, 7.73 dan 7.87 respectively; while moisture 16.93% ; acid insoluble ash 0.65%; total bacterial (TPC) 1.16 x103; E. coli, Salmonella sp., V. cholera and fungi were negative. According to the SNI 01-2891 BSN 1992, dried anchovy produced by using enclosed sun dryer better than dried anchovy produced by traditional method.

scholarly journals Study of Cracking Mechanism and Wear Resistance in Laser Cladding Coating of Ni-based Alloy

2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Zhenglei Yu ◽  
Lunxiang Li ◽  
Deqiang Zhang ◽  
Guangfeng Shi ◽  
Guang Yang ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Wear Resistance ◽  
Rare Earth ◽  
Fracture Mechanics ◽  
Composite Coating ◽  
Laser Cladding ◽  
Rare Earth Oxide ◽  
Cracking Mechanism ◽  
Crack Susceptibility ◽  
The Rare Earth

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.

scholarly journals Fe–Si–Al Coatings with Stable Wear Resistance Prepared by Laser Cladding Industrial Wastes

Metals ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 96 ◽  
Author(s):  
Xue Liu ◽  
Bin-Bin Ma ◽  
Li-Wei Hu ◽  
Jin-Feng Li ◽  
Feng-Sheng Qu ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Carbon Steel ◽  
Laser Cladding ◽  
Low Cost ◽  
Industrial Wastes ◽  
Solid Solution Phase ◽  
Steel Matrix ◽  
Wear Resistant Coatings ◽  
Low Mass ◽  
Columnar Grain

Because wear is one of the most common reasons for the failure of metals, the development of a low-cost coating with enhanced wear resistance is of great importance. In the present study, Fe–Si–Al coatings with superior and stable wear resistance were prepared by laser cladding Fe–Si–Al industrial waste onto 1045 carbon steel. The microstructure, as well as the wear mechanism of the Fe–Si–Al coatings, was investigated. The Fe–Si–Al coatings consist of a (Al, Fe, Si) solid solution phase in both columnar grain form and equiaxed grain form. The Fe–Si–Al coatings possess enhanced microhardness of 494 ± 15 HV0.3 and low mass loss of 5 × 10−5 mg·(N·m)−1. The wear resistance is ten times higher than that of the 1045 carbon steel matrix. The wear of the Fe–Si–Al coatings is mainly dominated by abrasive wear and adhesive wear. This work provides important insight into the preparation of low-cost, wear-resistant coatings, as well as stable, superior wear resistance.

scholarly journals Message Broadcasting via a New Fault Tolerant Irregular Advance Omega Network in Faulty and Nonfaulty Network Environments

2013 ◽  
Vol 2013 ◽  
pp. 1-16 ◽  
Author(s):  
Ved Prakash Bhardwaj ◽  
Nitin
Keyword(s):  
Fault Tolerant ◽  
Interconnection Network ◽  
High Reliability ◽  
Low Cost ◽  
Routing Algorithm ◽  
Multiple Faults ◽  
Message Broadcasting ◽  
Double Switch ◽  
Better Than

Interconnection Network (IN) is a key element for all parallel processing applications. Multistage Interconnection Network (MIN) is an efficient IN for these applications, as it has the quality of excellent performance at low cost with high reliability. MINs are effective medium for message broadcasting. Doing the same task in faulty situations is a critical challenge. In this paper, we have presented a new Fault Tolerant Interconnection Network named as Irregular Advance Omega Network (IAON); also we have presented its routing algorithm. IAON is the modified form of Advance Omega Network. The proposed MIN can endure multiple faults and provides a suitable path between every source to every destination. We have examined the fault tolerance capacity of IAON and compared its performance with other existing MINs. In order to check the performance of proposed MIN, message broadcasting was performed in three conditions as follows: (1) when network was fault free; (2) when network was Single Switch Faulty in every stage; (3) when network was Double Switch Faulty in every stage. Results showed that IAON performed better than the earlier proposed MINs.

PHASE CONSTITUENTS AND MICROSTRUCTURE OF Ti3Al/Fe3Al + TiN/TiB2 COMPOSITE COATING ON TITANIUM ALLOY

2011 ◽  
Vol 18 (03n04) ◽  
pp. 103-108 ◽  
Author(s):  
JIANING LI ◽  
CHUANZHONG CHEN ◽  
CUIFANG ZHANG
Keyword(s):  
Wear Resistance ◽  
Titanium Alloy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Composite Coating ◽  
Laser Cladding ◽  
X Ray Diffraction ◽  
X Ray ◽  
Laser Cladding Process ◽  
Scanning Electron

Laser cladding of the Fe3Al + B4C/TiN + Al2O3 pre-placed powders on the Ti-6Al-4V alloy can form the Ti3Al/Fe3Al + TiN/TiB2 composite coating, which improved the wear resistance of the Ti-6Al-4V alloy surface. In this study, the Ti3Al/Fe3Al + TiN/TiB2 composite coating has been researched by means of X-ray diffraction and scanning electron microscope. It was found that during the laser cladding process, Al2O3 can react with TiB2 , leading to the formations of Ti3Al and B . This principle can be used to improve the Fe3Al + B4C/TiN laser-cladded coating on the Ti-6Al-4V alloy. Furthermore, during the cladding process, C consumed the oxygen in Fe3Al + B4C /TiN + Al2O3 molten pool, which retarded the productions of the redundant metal oxides.

Experimental Study on Single-Layer Laser Cladding Feeding by Micro/Nano Composite Powders

2013 ◽  
Vol 562-565 ◽  
pp. 958-963
Author(s):  
Ming Di Wang ◽  
Shi Hong Shi ◽  
Hong Yu Wang ◽  
Cheng Feng Sun ◽  
X.B. Liu
Keyword(s):  
Mechanical Properties ◽  
Experimental Study ◽  
Laser Cladding ◽  
Single Layer ◽  
Composite Powders ◽  
Nano Composite ◽  
Cladding Layer ◽  
Nanocomposite Powders ◽  
Better Than

Aimed at the lack of the cladding materials such as micro or nanopowder, the micro/nanocomposite powders prepared for experiment are feed directly, the key process parameters on the quality of the surface quality and microstructure analysis of the single-layer of laser cladding are studied in detail. Compared to the ordinary laser micro-cladding layer feeding by the micro powder, the cladding layer is more refined, which has more good mechanical properties. The results showed that: using reasonable parameters, the microstructure and macro-morphology of cladding layer with micro-nanocomposite powders feed directly are better than of micron powders.

scholarly journals Selection of modes for laser cladding of PR-08Kh17N8S6G powder

2020 ◽  
pp. 46-51
Author(s):  
A. N. Gots ◽  
◽  
A. B. Lyukhter ◽  
D. S. Gusev ◽  
A. V. Zavitkov ◽  
...  
Keyword(s):  
Contact Angle ◽  
Laser Cladding ◽  
Mixing Layer ◽  
Experimental Studies ◽  
Radiation Processing ◽  
Unique Identifier ◽  
Variable Parameters ◽  
Laser Cladding Process ◽  
Coaxial Feed

A brief analysis of powders used in the industry for surfacing on the work surfaces of critical parts is given in order to increase their wear resistance. The results of experimental studies on the choice of parameters of gas-powder cladding modes are presented. The cladding process was carried out by a laser robotic complex with a coaxial feed of powder to the surfacing zone. The substrate used steel grade 08H18N10T, which was applied to the melt of wear-resistant powder grade PR-08H17N8S6G. The use of ytterbium fiber laser allowed to reduce the heat supply to the surfaces, which significantly reduced the residual stresses in the workpiece. Variable parameters of the laser cladding process were the output power of laser radiation, processing speed, and powder mass flow rate. During visual inspection, the absence of pores and cracks were used as the estimated indicators of the cladding. The study of macro geometry single clad track was conducted on cross section of the clad. During measurements, the quality of a single clad track was determined by its geometric dimensions: clad height, clad width, contact angle between the tangent to the cladding surface and the substrate plane, as well the depth of the mixing layer of the surfaced and substrate materials. According to the results of experimental studies of the selected optimal mode, providing a cladding track with a clad height above 1 mm; clad width 2.5 mm; the depth of the mixing layer – 0.2 mm; contact angle between the tangent to the clad surface and the substrate more than 50º. This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation. Agreement on the provision of subsidies No. 075-15-2019-1833 dated December 03, 2019. Unique identifier PNI RFMEFI60419Kh0245.

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