Laser-Assisted coating techniques and surface modifications: a short review

Madey

et al. 2022

JMSE

In this study, a method for ensuring reliable and safe operation of marine trunk diesel engines is considered. The research was carried out on 5L23/30 MAN-B&W diesel engines of a Bulk Carrier class vessel. The objective of the study was to determine the effect of the structural characteristics of the oil layer (wetting angle and thickness) on the operational parameters of a marine diesel engine (compression pressure, concentration of nitrogen oxides in exhaust gases and temperature of exhaust gases after the cylinder) and performance characteristics of the oil (base number, wear and contaminant elements). It has been established that an increase in the degree of the contact angles of wetting and in the thickness of the oil layer improves the heat and power and environmental performance of a diesel engine. At the same time, the decrease in compression pressure in the cylinder slows down, the temperature of gases after the cylinder decreases, and the emission of nitrogen oxides with exhaust gases decreases. Also, it was found that wear of diesel parts and oil oxidation are reduced. The study confirms the possibility of improving the reliable and safe operation of trunk-type diesel engines of maritime vessels by effective control of variables relating to the characteristics of engine oil.

Section: Literature Reviewmentioning

confidence: 99%

Ensuring Reliable and Safe Operation of Trunk Diesel Engines of Marine Transport Vessels

Madey

et al. 2022

JMSE

“…Laser cladding exploits the high energy density of a laser beam to melt and spray metal powder (or wire) onto the surface of the target substrate, forming coatings with high hardness, high abrasion resistance, high corrosion resistance, etc. The cladding process enables surface modification of critical parts as well as the repair of surface damage, and it has been widely used in the fields of aviation, aerospace, automotive, machinery and so on [1,2].…”

Section: Introductionmentioning

confidence: 99%

Comparative assessment of supervised machine learning algorithms for predicting geometric characteristics of laser cladded inconel 718

Yang,

Geng,

Alfano

et al. 2024

Mater. Res. Express

Laser cladding, an innovative surface modification and coating preparation process, has emerged as a research hotspot in material surface modification and green remanufacturing domains. In the laser cladding process, the interaction between laser light, powder particles, and the substrate results in a complicated mapping connection between process parameters and clad layer quality. This work aims to shed light on this mapping using fast evolving machine learning algorithms. A full factorial experimental design was employed to clad Inconel 718 powder on an A286 substrate comprising 64 groups. Analysis of variance, contour plots, and surface plots were used to explore the effects of laser power, powder feeding rate, and scanning speed on the width, height, and dilution rate of the cladding. The performance of the predictive models was evaluated using the index of merit (IM), which includes mean square error (MSE), mean absolute error (MAE), and coefficient of determination (R2). By comparing the performance of the models, it was found that the Extra Trees, Random forest regression, Decision tree regression, and XGBoost algorithms exhibited the highest predictive accuracy. Specifically, the Extra Trees algorithm outperformed other machine learning models in predicting the cladding width, while the RFR algorithm excelled in predicting the associated height. The DTR algorithm demonstrated the best performance in predicting the cladding dilution rate. The R2 values for width, height, and dilution rate were found to be 0.949, 0.954, and 0.912, respectively, for these three models.

“…Frictional wear is one of the factors of mechanical component damage, which brings great economic losses to the industrial field, especially from the wear of metallic materials [1]. This has been an important topic in the industry, agriculture, mining, aerospace, and other fields [2].…”

Section: Introductionmentioning

confidence: 99%

High-temperature wear behaviour of ZrC/NbC-reinforced CrMnFeCoNi coatings

Sun

Cai

Zhu

et al. 2022

Surface Engineering

Nowadays, studies of high entropy alloys (HEAs) have shown excellent properties. To improve the high-temperature wear resistance of CrMnFeCoNi alloy, refractory carbides (NbC and ZrC, respectively) reinforced CrMnFeCoNi composite coating were prepared by laser cladding (LC), and its wear performance was investigated. The composite coating showed no cracks or other defects that had metallurgical bonding with the substrate. Those coatings exhibited oxidative and adhesive wear mechanisms in reciprocating wear tests at 600°C. In contrast to the strengthening of NbC, the ZrC in the coating rapidly oxidized during high-temperature wear, forming a large amount of ZrO 2 . These oxides formed in wear promote the formation of a protective film, further improving the oxidation resistance and wear resistance of the coating.