Prediction of the Adhesion Strength of Coating in Plasma Spray Deposition

Abstract

The goal of this work is to validate the existing plasma spray mathematical models, using a calculation method and the comparison with experimental data, in order to determine their validity. A preliminary evaluation of the adhesion based on the velocity and temperature of the particles is useful to be calculated by using the mathematical model. Given the thermal-physical properties and chemical composition of a Fe-based amorphous X-5 powder, a modified model was suggested. For comparison, a series of experiments using plasma spraying of the X-5 powder were conducted. The significance of the current study consists of the model validation by using the data of the plasma spraying of the Fe-based amorphous material as a potential substitution for saving production costs by using ordinary air as the plasma generation gas. The findings show the discrepancy between the models and the experimental results. The prediction of adhesion using the mathematical models does not cover essential parameters such as the enthalpy of the particle stream. It is necessary to improve the mathematical models, including the modified one, based on the experiment results, with different pairs of particles and substrate materials. The proposed formula is applicable during the preliminary design of the spray process and the development of a new torch construction.

Optimization of Technological Parameters when Plasma Nitriding the Gear Working Surface

“…An analysis of variance (ANOVA) was carried out on the regression equation results, to remove the parameters that do not affect them [11,14,[16][17][18][19][20][21][22][23][24]. The regression equation for hardness H can be written as follows: 2726 6.44 ℎ 10.52 87.17 1.090 ℎ 0.00776 0.690 ℎ 1 0.1552 1…”

“…The permeation process with samples of the same material and size changes little the permeation temperature TL, so the voltage V and pressure P were fixed [1,11,26]. The temperature rise rate of the part over time TG, furnace wall temperature TW, and temperature rise rate of the furnace wall over time WG depend on permeation temperature TL and permeation time h. Gas permeation flows G1, G2, G3, and G4 are proportional to each other [26].…”

“…This ion bombardment heats, cleans, and forms a hard layer with good wear resistance, increasing fatigue strength [7]. In recent years, many studies have been conducted on the nitriding process model, but it is generally not enough to predict the influence of the parameters on the quality of the permeable layer [3][4][5][9][10][11][12][13].…”

“…Several studies attempted to predict and evaluate the distribution of nitrogen concentrations and nitride compounds formed during pure iron nitriding and the depth of the nitrogen diffusion area after plasma nitriding [3,8,16]. As the plasma power increases, the maximum adhesion values change, reaching 80MPa when the plasma power approaches 80kW [11]. In [12], the influence of plasma nitriding technology parameters on the deformation of hypoid gears was investigated, using blue light technology with a non-contact measuring device to determine the deformation after plasma nitriding.…”

“…This study used an ELTROPUL permeation furnace with a premade plasma pulse source with stable plasma flow in all cases and easily penetrating details with complex geometries. Along with mathematical statistics tools and Minitab software, methods such as EDAS, MARCOS, TOPSIS, MOORA, and PIV [11][12][13][18][19][20][21][22][23][24][25] were used to design and process the experimental data of this study.…”