Wear resistant steels

Abstract

Everyone knows, approximately, what wear is; however, wear is not an exact science. 1 Its minimisation in innumerable industrial operations and products would present substantial economic benefits. A useful, general definition is the progressive loss of material from the surface of a solid body due to mechanical action, i.e. the contact and relative motion against a solid, liquid or gaseous counterbody. 2 Various modes of wear have been defined 2,3 : adhesive, abrasive, surface fatigue and tribochemical reaction, each with its own sub-divisions, whilst noting that they often occur in combination. Other authors have added extra sub-divisions, or even extra categories which it could be argued are cases (albeit conveniently) combining elements of the existing definitions. A whole paper could be spent, or maybe wasted, trying to define and argue these, but that is not the purpose here. Suffice it to say that wear is a property: 'characteristic of the engineering system', 3 rather than purely a material property, which itself raises significant issues as to how to measure it most relevantly for the application in question. 2,4 Hardness has long been known as a key material property for wear resistance, but by no means a sufficient one, 5 but which is often achieved with a reduction in other desirable properties, notably ductility. Although wear is a mature subject and steel a mature material, both continue to benefit from further understanding and development, with major economic implications.The declared target for the contributions to this thematic issue was new steel developments from the laboratory stage up to and including trial applications, and the state of current research on the material aspects of obtaining good wear resistance in combination with improvement of other mechanical properties. Surface treatment of the steel was within scope but not coatings as such.Clearly, this target could not be met exhaustively for such a wide, active and important field. However, interesting contributions were received on a range of different aspects.

Toward the Development of AHSS for Wear Resistant Applications

“…The hardness levels of the austempered high-Si steel were lower than expected, so the results of this study did not provide a clear comparison of the austempered and Q&P microstructures, both containing substantial austenite. Other laboratories are developing wear-resistant microstructures through similar process/microstructure concepts, demonstrating the increased attention on extension of AHSS concepts to non-automotive steels [9][10][11][12].…”

Wear behaviour at 600°C of surface engineered low-alloy steel containing TiC particles

“…The increasing demand for material for hightemperature wear applications has concentrated attention on improving the surface properties, by modifying the surface composition of the substrate [1][2][3][4][5]. If the material used is below the required specification, the consequences may be devastating, as the operating system can easily lose the permissible tolerance, leading to malfunction.…”

“…If the material used is below the required specification, the consequences may be devastating, as the operating system can easily lose the permissible tolerance, leading to malfunction. Several materials such as titanium alloys, aluminium alloys and carbon steels are known for their proneness to severe wear, due to their reduction of hardness and strength from thermal softening effects, and require surface reinforcement, especially when operating at high temperatures [1][2][3][4][5][6][7]. To overcome these problems, the ubiquitous tungsten inert gas (TIG) technique that is cheap, flexible and low in operating and maintenance costs has been used to develop superior surfaces to the parent materials compared to the expensive and complex lasers or electron beam techniques [6][7][8][9][10][11][12][13].…”