Effects of Vanadium on Microstructure and Wear Resistance of High Chromium Cast Iron Hardfacing Layer by Electroslag Surfacing

Abstract

The 3.6C-20Cr-Fe-(0-2.32)V high chromium cast iron (HCCI) hardfacing layers were deposited on low alloy steel by electroslag surfacing. The microstructure of hardfacing layers were observed and the carbide types, size and area fraction were measured. In addition, the hardness and wear resistance were tested. Results show that the interface between hardfacing layer and low alloy steel is defect free. 3.6C-20Cr-Fe hardfacing layer contains primary carbides and eutectic. Increasing V wt % in the hardfacing layer, primary carbides are decreasing by increasing eutectic along with martensite formation. For 1.50 wt % of V, the microstructure contains a lot of eutectic and a little of martensite. For 2.32 wt % of V, primary austenite formed, the microstructure is primary austenite, eutectic and a little of martensite. In the V alloyed hardfacing layers, V has strong affinity with carbon than chromium, hence V can replace a part of Cr in M 7 C 3 and (Cr 4.4-4.7 Fe 2.1-2.3 V 0.2-0.5)C 3 type carbides are formed. When the V is 2.32 wt %, (Cr 0.23 V 0.77)C carbides are formed in the hardfacing layer. The hardness and wear resistance are improved by increasing V from 0 to 1.50 wt %. However, when the V is 2.32 wt %, the primary austenite has reduced the hardness and wear resistance of hardfacing layer.

Surfacing – Technologies and Layer Properties (A Review)

“…However, there are also technological variants that differ significantly from welding and are not applicable to joint parts. Thus, the thickest layers are obtained by electroslag surfacing (ESS) [1]. In this case, as with submerged arc surfacing (SAS) [5], [6], [7], [19], the layer characteristics are obtained depending on the combination of the components contained in the flux and the additive wire.…”

“…divided into the following main groups. The microstructure is examined by optical (OM) [1], [9], [17], [21], [23], [27], [30], [31], [36] ], [42], [43] and electron microscopy (SEM) [1], [10], [11], [14], [21], [22], [23] , [33], [39], [46], [47]. The phase composition is determined by the X-ray diffractometer [18], [23], [27], [31], [33], [36], [39], [45], the transmission diffraction electron microscopy [18] and energy-dispersive X-ray spectroscopy [14], [22], [30], [33], [39].…”

“…The X-ray fluorescence method [7] and the atomic emission spectrometer [7] were used to determine the chemical composition. Image analysis is used to determine the relative share of individual components [1].…”

“…In the publications reviewed, the materials used as substrates can be divided into the following main groups: carbon steels [3], [6], [7], [12], [13], [15], [16] 17, 18, 21, 25, 26, 29, 36 and 37; alloyed steels [1], [4], [8], [9], [20], [22], [24], [30], [41] and [42]; highly alloyed steels [5] and [32]; aluminium and aluminium alloys [11], [28], [39], [43], [44] and [45]; titanium and titanium alloys [23], [31], [34] and [35]; ductile cast iron [33] and [40]. The SAS, MIG / MAG, TIG, PST, EBS and LS methods were used to apply the layers to carbon steels.…”

“…Highest thickness layers are obtained using electroslag surfacing. The process for depositing high-chromium cast iron on low-alloy steel is described [1]. The chemical composition of the applied layer is shown in Table 1 [1].…”