Study of Adhesion in Steels Surface Hardened

Abstract

This study evaluates the adhesion of boride layers on the surface steels of AISI 4140, 8620, W2 and H13 by standard VDI 3198 [1], the surface hardened was carry out by the technique of power pack boriding at the temperatures of 1273 K, with time exposition of 6 and 8 h. The presence of boride phases was determinate by X-ray diffraction (XRD) analysis. A Rockwell C indentation tester was applied on the surface steels boriding, this impact test determines qualitatively the adhesion on layer/substrate indentation print and Vicker microhardnes was evaluate a load of 2.9 N on phase FeB and Fe2B, the steels have scale delamination H1 to H6.

Characterization of Adherence Steels Hardened Superficially

“…Steels AISI 8620 and AISI 1018, some small cracks are identified, however with sufficient adherence, referring to the German standard adherence (Daimler Benz Adherence Test). There is a presence of FeB phase in these steels, which is prone to cracks easily generate their hardness and hard coating due to the mechanical action of hardness testing, in turn generated by tensile residual stresses in these steels [17]. …”

Characterization of bilayer (FeB/Fe2B) on AISI H13 work tool steel

“…In order to enhance the tribological performance of AISI H13 steel exposed to extreme wear conditions, the boriding process is needed to get hard boride layers on the surface of this material that meet the wanted requirements in the industry. For this reason, some studies were devoted to the boriding of AISI H13 steels [5,6,[8][9][10][11][12][13][14] under different boriding conditions. For indication, Taktak [5] has pack-boronized the AISI H13 steel in the range of 1073 to 1223 K during 3, 5 and 7 h. The maximum layer thickness of (FeB + Fe 2 B) was about 45 µm with calculated value of activation energy of 244.37 kJ mol -1 .…”

Evaluation Hard Layers in Steel AISI 8620

“…Currently manufacturing industries are requiring materials have increased component life industrial use manufacturing processes primary and secondary, requiring also high performance materials to cut costs increase productivity thereby and producing pieces [1][2]. This will need to obtain hard layers, as the Thermochemical treatments boriding obtained as iron boride layers, these layers formed on the surface tend to reduce the coefficient of slippage, wear resistance and erosion of tooling and engineering parts [3][4]. On the other side have increased investigations, studies and characterization of hard coatings by various techniques to obtain layers of high strength and toughness [5].…”