Abrasive Wear Of Steel Research Articles

Физико-механические аспекты абразивного изнашивания сталей в условиях охлажденной воздушной среды

Физико-механические аспекты абразивного изнашивания сталей в условиях охлажденной воздушной среды

Effect of tensile properties on the abrasive wear of steel saw wires used for silicon ingot slicing

The abrasive wear patterns and the tensile properties of steel saw wires (120μm in diameter) were investigated in order to develop highly reliable saw wires for the application to silicon (Si) ingot slicing. Saw wires that underwent heat treatment at different linear velocities during the patenting process were subjected to 2-body abrasive wear (2-BAW) and 3-body abrasive wear (3-BAW) tests. The 2-BAW and 3-BAW tests of the saw wires showed opposite trends in abrasive wear resistance. The wear loss resulting from the 2-BAW test was mainly determined by the tensile strength and microhardness of the steel saw wire samples, while the wear loss from the 3-BAW test was primarily determined by the elongation, or ductility, of the samples.

Abrasive wear of steel against gravel with different rock–steel combinations

Wear testing equipment and tests used in research laboratories are often miniature or simplified versions of real applications. For example standardized ASTM dry sand rubber wheel abrasion test G 65 and pin abrasion test G 132 are widely used to study materials’ abrasion wear resistance. The test results, however, do not always correlate too well with the results obtained from real wear conditions. One reason for this is, for example, that in the crushing applications of mining industry the abrasive size is usually much larger than that used in the laboratory wear tests. To study the abrasive wear caused by larger size gravel, new three-body abrasion test equipment was therefore constructed. The equipment uses the pin-on-disk principle with free abrasive particles of sizes up to 10 mm. During the test the pin is repeatedly pressed against a fixed amount of abrasive that is rotating with the disk having confining walls. As the pin is prevented from touching the counterbody, only the abrasive acts as the wearing agent. Three steels of different hardnesses were cross-tested as pin–disk pairs and as pins against a rubber disk using three igneous rock gravels with different crushability properties as abrasives. The wear was measured as mass loss from both the pin and the disk, and the rock comminution was measured by sieving. The results indicate that the mechanism of wear is greatly affected by the hardness of the counterbody. When using large size abrasives, the rate of comminution is also a very important factor that can significantly affect the wear test results.

Abrasive wear of steels in handling of bulk particulates: an appraisal of wall friction measurement as an indicator of wear rate

The advantages of using wall friction instead of hardness to indicate likely relative wear rates are given consideration and discussed. The results of sliding abrasive wear tests on a variety of commercially available steels using two particulate solids are presented, together with the results of wall friction tests between the same steels and one of the particulate solids. Correlations found between the wear rates and wall friction data are presented, and are shown to hold for both particulate solids.

The Influence of Stress State on the Abrasive Wear of Steels

The Influence of Stress State on the Abrasive Wear of Steels

Influence of stress state on abrasive wear of steels

The resistance of materials to abrasive wear depends on many factors that can be generally classified as material-based or operating systembased. In the published wear models, the bulk stress state or stress history of worn material do not appear as influencing factors. Following the analogy with stress corrosion and fatigue, as well as with cyclic softening of steel materials, the possible influence of bulk stress state and stress history on abrasive wear of steels has been examined. Preliminary experiments were carried out using a scratch tester with a diamond indenter. Hypoeutectoid steel specimens were bent to obtain tensile or compressive stress and then scratched in situ under a normal load of 25–40 N. The results of the screening experiments indicate that the depth of grooves and the wear mechanism differ, depending on whether the specimens are under tension or compression. Tensile stress favours micro-cutting, while a compressive state apparently maintains microploughing. The pilot experiments,conducted with a hypereutectoid steel, indicate (with a confidence 80%) the significant influence of stress history, i.e. cyclic stressing, on abrasive wear. Further analyses, combined with detailed observation using scanning electron microscopy, have allowed discussion and explanation of these phenomena.

Abrasive wear of steel in molding equipment

Experimental studies of the wear resistance of steel 45 with a strengthened surface in the abrasive mass used as raw material for the porcelain-faience industry were conducted. The results of the studies can be used for selecting a method of strengthening of molding equipment.

Abrasive wear of steels against silica-filled epoxy resins under combined rolling and sliding motion

The abrasive wear of carburized and uncarburized low-alloy steels has been studied under conditions of combined rolling and sliding motion against a range of composite counterfaces containing a high proportion of silica particles in an epoxy resin binder. The system simulates some aspects of abrasion by natural rocks. The wear rates of the steels depended strongly on the compressive strengths of the composites: increasing the strength of the composite reduced the wear rate of the steel. The extent of sliding motion had little effect on the wear rates per unit sliding distance. The wear rates of the composites also varied widely, and depended not only on their bulk strength butr also on the porosity level and filler/matrix bond strength. Removal of material from the composite counterface, leading to the exposure of fresh abrasive particles, occurred more readily for the weaker composites and led to the higher wear rate of the steel. On the stronger composites an accumulation of metallic debris contributed to reduced wear rate in the steel. The mechanisms and rates of degradation of the composites were very important in determining the abrasive wear rates of the steel specimens.

The abrasive wear of steel during rolling-sliding contact with rock counterfaces

In many mining operations ( e.g. excavation, drilling, tunnelling, rock crushing), metallic components are forced against abrasive rocks in a complex motion. This study examines the relative importance of combined rolling and sliding motion in the two-body abrasive wear of a low carbon tempered martensitic steel against rock counterfaces. A novel wear test rig has been used to vary the amount of rolling and sliding motion between a rotating steel cylinder and a counter-rotating sandstone (highly abrasive) or limestone (much less abrasive) disc. Weight loss measurements reveal that the wear rate of the steel increases as the amount of motion against the rock counterface is reduced from pure sliding to about 50% sliding (and about 50% rolling). With further reductions in the amount of sliding motion, the wear rate of the steel is reduced because of the formation of corrugations on the sandstone and limestone rock surfaces. Scanning electron microscopy shows that when the amount of motion is reduced from pure sliding to about 50% sliding, the topographical and subsurface physical properties of the worn steel and rock surfaces are modified. Following large amounts of sliding motion (70–80% sliding), the worn steel surface is heavily deformed by shearing in the sliding direction and many of the minerals in the worn rock counterface are crushed and compacted. Reducing the motion to 50% sliding leads to a reduction in the depth of the plastically sheared layer in the worn steel, and the rock surface shows a considerable reduction in the amount of mineral crushing and compaction, with many of the abrasive grains maintaining some angularity. It is concluded, therefore, that the increasing wear rate of the steel with the amount of rolling motion, until the onset of rock surface corrugations, probably results from the rock counterface retaining a higher proportion of angular abrasive minerals.

The abrasive wear of steels in South African soils

A high carbon steel was heat treated to produce a range of microstructures and mechanical properties. These steels were subjected to abrasion testing in stony, clay, and sandy soils. Wear rates were found to be twenty times higher in stony soil than in sandy soil and seven times greater than in clay. It was found that the relative wear resistance increased in sandy and clay soils with increase in steel hardness. In stony soils the relative wear resistance of all steels was found to be similar. An explanation for such behaviour was formulated on the basis of surface temperature heating and work hardening effects. The aggressive nature of abrasion found in stony soils was also found to give rise to the appearance of very hard white layers on the steel surfaces.

Effect of temperature on the wear resistance of steels with metastable austenite

1. In tests at 20–250° the wear resistance of steel Kh12F1 with a stable α structure is independent of the testing temperature. 2. The resistance to abrasive wear of steels with retained metastable austenite varies greatly with the testing temperature. With increasing temperatures the completeness of the γ→α transformation, hardening, and wear resistance decrease.