The Experimental and Numerical Research for Plastic Working of Nickel Matrix Composite Coatings

Abstract

In the machine, metallurgical, and shipbuilding industries, steel products with alloy and composite coatings based on nickel may be used. It is expedient to improve the physicochemical properties of the surface layer of products as they have a significant roughness value after thermal spraying. It is therefore important to finish the layers applied by flame spraying, where machining is used for this purpose. However, it causes a loss of coating material, which is quite expensive. Therefore, in order to reduce costs and improve the quality of the surface layer, the finishing treatment of nickel-based coatings by means of plastic working is used. Two types of plastic working were proposed: rolling and burnishing. Numerical and experimental tests of the plastic processing of alloy coatings were carried out. The roughness of the coatings after rolling decreased to 1/25 and 30% strengthening of the alloy coating matrix was determined. After burnishing, roughness was reduced to 1/12 and the alloy coatings were strengthened by 25%. Plastic working by rolling and burnishing has a beneficial effect on the surface quality of the workpiece, not only by significantly improving the roughness, but also by increasing the strength properties of the surface layers.

After-Machining Surface Layer of Composite Coatings Obtained by Thermal Spraying

“…Ni-Al alloy and Ni-Al-Al 2 O 3 composite coatings, obtained by flame spraying, were investigated. The samples with shafts shape of steel C45 (ArcelorMittal, D ąbrowa Górnicza, Poland) (C-0.45%, Cr-0.4%, Mo-0.1%, Mn-0.7%, Si-0.3%, Ni-0.4%, P-0.045%, S-0.045%) [26] and spraying coatings were researched. The flame sprayed coatings were characterized by appreciable value of surface roughness.…”

Surface Characterization of Carbon Steel after Rolling Burnishing Treatment

“…Burnishing is one of the methods of finishing metals and their alloys, sinters and plastics, which involves the use of local plastic deformation [1][2][3], generated in the surface layer of the object [4][5][6][7][8][9], as a result of specific (force and kinematic) interaction of hard and a smooth tool (in the shape of a ball, disc, roller or other) with a machined surface [10][11][12][13][14][15][16][17][18]. The surface state and quality after previous treatment significantly depend on its quality after previous treatment [15][16][17][18][19].…”

“…In paper [4], the structure of the surface after burnishing and turning was analyzed, taking into account roughness parameters, as well as the photographs of the specimen surface and the bearing area curve. The steel products with alloy and composite coatings based on nickel with numerical and experimental tests of the plastic processing of alloy coatings were carried out in [5] and showed that after burnishing, the roughness was reduced to 1/12 and the alloy coatings were strengthened by 25%. Skoczylas et al [6,7] report the results of experimental studies on the impact of ball burnishing parameters on the roughness, microstructure and microhardness of the surface layer of laser-cut C45 steel parts.…”

Influence of Asymmetric Rolling Process on the Microstructure Properties of Bimetallic Sheet Metals

“…The preliminary assumptions made before the tests assumed that the introduced asymmetry of the circumferential rate of the work rolls would make it possible to obtain both a product with the desirable geometry and favorable mechanical properties of bimetallic materials. Depending on the type of material and deformation parameters, the effects of deformation strengthening can be removed by dynamic or static healing and (static, dynamic, and metadynamic) recrystallization [ 25 , 26 , 27 ]. During the rolling process, the phenomenon of dynamic recrystallization or dynamic recovery occurs during deformation [ 28 , 29 , 30 , 31 , 32 ].…”

“…Another problem with the uneven distribution of the deformation into the layers is the bending of the bimetallic band after it comes out of the rolling gap [ 11 , 18 , 20 ]. One of the methods of increasing the evenness of deformation of bimetallic sheet metals and obtaining a simple sheet metal is to introduce asymmetry of the peripheral speed of the work rolls (i.e., kinetic asymmetry) [ 17 , 25 , 30 ].…”