Abrasion Resistant Materials Research Articles

Method of improving the service properties of the plowshare frame using abrasion-resistant surfacing materials and polymer composites

The presence of intensive cultivation of agricultural crops in modern agriculture contributes to the in-creased wear rate of plowshares due to high plowing speeds. The use of well-known hardening methods is reduced to the use of hard alloys as coatings for working surfaces, which currently does not allow that currently does not allow to achieve a significant increase in the resource of the ploughshares, especially their frame (if the ploughshare is composite). The reason for this is the absence of an anti-abrasive coating over the entire volume of the friction surface of the part, which limits the working condition, which reaches 50 or more millimeters (undercutting-blade area). Such a significant value allows the use of various technological options to improve the resistance to abrasive wear, including the use of abrasion-resistant materials of different nature. Therefore, the task was to develop and test in real conditions the hardening technology, which provides a significant increase in abrasive resistance and durability, while maintaining the geometric parameters established by the technical conditions when performing agrotechnical requirements for tillage. The proposed technological process of hardening consists in surfacing the blade on the back side of the frame of the composite plowshare with a hard alloy. On the working surface, two rollers of increased hardness are formed along the edges of the blade and undercut areas, and the gap between them is filled with a glue-resin abrasive resistant composite. In this case, the entire area of the working surface (friction surface) of the undercutting-blade part is covered by reinforcing coatings (weld metal and composite). As a result of testing the developed hardening technology with the use of high-hardness alloys and an abrasion-resistant epoxy-based polymer composite with gravel filler, the durability of parts was increased by a factor of 1,6 compared with factory-made components.

Evaluation of the properties and structure of nanocrystalline surface layers in relation to selected constructional materials resistant to abrasive wear

The present paper is the result of the investigations of the properties and structure of nanocrystalline layers deposited from iron-based nanoalloy on steel S355N substrate by manual metal arc welding method (MMA) compared to selected abrasion-resistant construction materials currently used in industry. The resultant deposit welds were subjected to macro and microscopic metallographic examination. Working properties of obtained nanocrystalline deposits weld compared to currently used materials were evaluated based on the hardness, abrasive wear of metal-to-mineral. The results of deposits weld working properties measurements were compared with property of wear resistant steel HARDOX 400 type used as reference material.

Effect of matrix and hard phase properties on the scratch and compound behavior of wear resistant metallic materials containing coarse hard phases

Modern abrasion resistant materials, such as cold work tool steels, consist of higher amounts of hard phases embedded in a softer metallic matrix. Hence, the wear behavior is controlled by the mechanical compound properties, which are dependent on the single phase properties (e.g. hard phase type and matrix condition), volume content, morphology, and distribution. For the development of materials with adapted tribological properties and for a better understanding of the wear processes these influencing factors and their complex interactions must be known precisely. In this study, the effect of matrix and hard phase properties and volume content on scratch behavior and the mechanical compound properties are experimentally and numerically investigated for a hot work tool steel containing coarse hard phases. Spark Plasma Consolidation (SPC) was used to produce microstructures consisting of hot work tool steel matrix and different embedded hard phases. The matrix condition was controlled by subsequent heat treatment (hard and softer matrix condition). To analyze the single phase properties nanoindentation, scratch testing, and atomic force microscope investigations were conducted. Numerical simulations (Finite-Element-Method) show that the mechanical compound properties can also be predicted on the basis of measured single phase properties. The results reveal the interaction between single phase and compound properties and their effects on the scratch behavior.

Abrasion Wear Behavior of High-chromium Cast Iron

Abstract High-chromium cast irons are used as abrasion resistant materials. Their wear resistance depends on quantity of carbides and the matrix supporting these carbides. The paper presents the results of cast irons of chemical composition (in wt. %) 19–22 Cr and 2–4.5 C alloyed by 1.7 Mo + 5 Ni + 2 Mn to improve their toughness, which were tested in working conditions of ferroalloys crushing. Tests showed that these as-cast chromium cast irons with mostly austenitic matrix achieved the hardness of 38-45 HRC, but their relative abrasion resistance Ψ ranged from 1.3 to 4.6, was higher comparing to the tool made from the X210Cr12 steel heat treated on hardness 61 HRC. The transformation of austenite into martensite occurs not only at the worn strained areas (on a surface of scratch) but also in their neighbourhood. Due to the work hardening of relatively large volumes of transformed austenite the cast iron possesses high abrasion resistance also on the surfaces where low pressures are acting. The tough abrasion-resistant cast iron well proved for production of dynamic and wear stressed castings e.g., crusher hammers, cutting tools for ceramic etc.

ChemInform Abstract: Recent Progress of Abrasion‐Resistant Materials: Learning from Nature

AbstractReview: 50 refs.

Recent progress of abrasion-resistant materials: learning from nature.

Abrasion-resistant materials have attracted great attention for their broad applications in industry, biomedicine and military. However, the development of abrasion-resistant materials that have with unique features such as being lightweight and flexible remains a great challenge in order to satisfy unmet demands. The outstanding performance of natural abrasion-resistant materials motivates the development of new bio-inspired abrasion-resistant materials. This review summarizes the recent progress in the investigation of natural abrasion-resistant materials to explore their general design principles (i.e., the correlation between chemical components and structural features). Following natural design principles, several artificial abrasion-resistant materials have shown unique abrasion-resistant properties. The potential challenges in the future and possible solutions for designing bio-inspired abrasion-resistant materials are also briefly discussed.

Abrasion Resistance of as-Cast High-Chromium Cast Iron

Abstract High chromium cast irons are widely used as abrasion resistant materials. Their properties and wear resistance depend on carbides and on the nature of the matrix supporting these carbides. The paper presents test results of irons which contain (in wt.%) 18-22 Cr and 2-5 C, and is alloyed by 1.7 Mo + 5 Ni + 2 Mn to improve the toughness. Tests showed as-cast irons with mostly austenitic matrix achieved hardness 36-53 HRC but their relative abrasion-resistance was higher than the tool steel STN 19436 heat treated on hardness 60 HRC.

Long-Term Degradation of Composites Exposed to Liquid Environments in Agriculture

Abstract Polymeric particles composites with hard inorganic particles are abrasion resistant materials which can be used in the sphere of agriculture - e.g. for functional areas in renovation or as resistant layers. Silicon carbide waste particles were used in the present experiment, replacing the primary filler with waste without significant changes in the mechanical properties. The present paper describes the effect of immersion of polymeric particles composites with epoxy matrix in liquids on selected mechanical properties. Overall, it explains the change of hardness and resistance of abrasive wear, a typical kind of wear in the sphere of agriculture.

The Improved Design of Embedded CNC Milling Machine

The machining of complex shape workpiece embedded NC milling machine is suitable for all kinds of hard, brittle, thin products. This paper embedded CNC grinding machine design requirements, through the transmission gear, the workpiece clamping and buffering mechanism to improve the design, CNC system and abrasion resistant materials were optimized, so as to meet the requirements of high performance precision grinding machine.

Progress in Elaboration of Chemical and Abrasion Resistant Materials

Elaborations in the field of chemical and abrasion resistant coatings and composite polymer materials by company Polymate LTD.-INRC (Israel) and its employees are reviewed. The main fields of advanced corrosion resistance materials are liquid and water based rubber compositions, hybrid nonisocyanate polyurethane coatings, nanostructured organic-mineral coatings. The review includes patents used by the industry of several countries of Europe, USA, Canada and Asia.Chemical resistant materials, abrasion resistant materials, polymeric materials for coatings, hybrid nonisocyanate urethane-epoxides, nanostructured hybrid oligomer composition, rubber-based compositions, organic-mineral coatings.

High performance radiation curable hybrid coatings

Radiation curing is one of the most effective processes to produce rapidly composite materials at ambient temperature. Silica nanoparticles can be introduced into radiation curable resins to produce scratch and abrasion resistant materials, which can be used as sealants or clear coatings. In preparation of radiation cured polymeric composites for wood based products such as medium density fiberboard etc., we synthesized radiation curable silico-organic nanoparticles from silica/acrylates system. These nano-sized silica particles were used as fillers. Epoxy acrylates was used as prepolymer while pentaerythritol triacrylate and tetraacrylate (PETIA) was used as monomer. The acrylated epoxy resin synthesized from palm oil based product (EPOLA) i.e. bio-renewable raw materials was also used in the system. The surface of the silica was chemically modified to improve the embedding of the filler within the acrylate matrix. Modification of the silica surface using silane was done to overcome the problem of incompatibility with acrylates at high silica contents. The nature of the nanoparticles is now changed from hydrophilic to organophilic. In these investigations, we use low energy electron beam accelerator to initiate polymerization and interaction at the interface between the nanoparticles and the monomeric materials. These polymerization active nanoparticles were obtained by heterogeneous hydrolytic condensation of the silane to the silanol groups of the silica particles. Formulations useful for technical coating processes could be prepared and these composite materials showed highly improved mechanical properties. They also provided a high network density whilst the coatings remain transparent. These polymeric nanocomposites show excellent resistances toward abrasion properties including scratch property as compared to pure acrylates.

Modeling Abrasion Resistant Materials by Modeling Large Sliding Frictional Contact

— In this paper, our goal is to simulate abrasion resistance material. We therefore need a robust algorithm to model this phenomenon which is a kind of large frictional contact problem. In order to reach to our aim, we have proposed a new method to impose contact constraints in eXtended Finite Element Method (XFEM) framework. In this algorithm, we have modeled large sliding contact problems by using the Node To Segment (NTS) concept. Furthermore, friction between two sliding interface has been modeled based on the Coulomb friction law. In addition, the penalty method which is the most convenient way of imposing non-penetration constraints has been employed. In our algorithm, new Lagrangian shape functions have been used to solve the problems of the conventional Heaviside enrichment function. Finally, a numerical simulation has been delivered to prove the accuracy and capability of our new algorithm.

Advances in the Development of Carbidic ADI

Carbidic ADI (CADI) is a new type of Austempered Ductile Iron containing free carbides in the microstructure, providing a particular combination of wear resistance and impact toughness. In this work, four CADI variants were evaluated, in which carbides were promoted by alloying with chromium. Tests performed under the low stress abrasion condition imposed by the ASTM G65 standard show that CADI can increase the wear resistance up to 100 % when compared with conventional ADI austempered at the same temperature. The carbide content must be higher than 10 % to promote a considerable reinforcing effect. However, at this carbide content level, the impact toughness varies between 7 and 11 J/cm2 for unnotched samples. These values are much lower than those of conventional ADI, but higher than those of other abrasion resistant materials, like white irons. Some CADI variants were also evaluated in field tests, producing abrasion under either low stress or high stress conditions. For this purpose, two CADI prototype parts were studied: screw segments for animal food extruders (low stress abrasion) and wheel loader bucket edges (high stress abrasion). The results gathered showed that CADI behaves satisfactorily under low stress abrasion, but the performance is not so good under high stress conditions. To analyze the differences in the abrasion response, scratch tests were performed in order to evaluate the interaction between the abrasive tip and the microstructure.

A Study on the Effects of Heat Treatment to the High-Carbon HSS Roll

High-carbon high-speed steels (HSS) are extremely abrasion resistant materials due to their high hardness MC type carbide and high hardness martensitic matrix. Different microstructures and mechanical behaviours were obtained after the quenching and tempering temperatures of HSS roll were changed. With air cooling and sodium silicate quenching, when the austenitizing temperature reaches 1273K, the metal matrix all transforms into the martensite, Afterwards, the eutectic carbides dissolve ceaselessly into the metal matrix and its continuous network distribution changes into broken network. The peak hardness temperature of high-carbon HSS is around 1323K, and the second hardening temperature is around 793K. No significant change in tensile strength and elongation percentage was observed unless the tempering temperature is beyond 753K. The tensile strength is increased obviously and the elongation percentage is decreased slightly beyond 753K. However, the tensile strength is decreased and the elongation percentage is increased when the temp exceeds 813K. The high-carbon HSS roll presents excellent abrasion resistance at 793K-813K.

Design and fabrication strategy in the world of functional gradation

The concept of Functionally Graded Materials, FGM, was introduced in 1980s for the development of reliable thermal shock resistant components for high temperature applications. Later on biomimetic approaches were included, to arrive at multifunctional, multiscale FGM's for numerous applications, including abrasion resistant materials and materials for implants. The paper briefly reviews the past achievements and highlights future trends in multi-scale graded materials science and technology, with the aim at utilisation of bio-inspired methods in design and fabrication strategy. Examples are given for systems with hierarchically graded porosity for application in hard tissue implants and in diesel engine filters, respectively.

Influence of heat and thermochemical treatment on abrasion resistance of structural and tool steels

Abrasive wear is responsible for intensive degradation of machine parts or tools. This process starts as an interaction between hard, mostly mineral, particles and the working surface. Methods of increasing the lifetime are based on application of abrasion resistant materials or creation of hard, wear-resistant surface layers or coatings on the surfaces of machine parts or tools. Carbon and low-alloy steels with different types of thermochemical treatment (case hardening, nitriding) are used in cases of low abrasion. Another method of increasing lifetime is the application of ledeburitic steels. The wear resistance of these steels depends on their chemical composition and heat treatment. The results of laboratory tests of thermochemically treated steels, heat-treated ledeburitic chromium steels and high-speed steels show the effect of the microstructure of these steels on their abrasion resistance. Abrasion resistance of carburized low-alloy steels is on the same level as in high-carbon structural and tool steels. In ledeburitic chromium steel maximum abrasion resistance was achieved by quenching from 1100 °C whilst in ledeburitic chromium–vanadium steel the optimum quenching temperature was 1150 °C. Growing abrasion resistance was caused by increasing amounts of retained austenite.

Development of Scratch- and Abrasion-Resistant Coating Materials Based on Nanoparticles, Cured by Radiation

The aim of this study was to compare the effect of monomers, prepolymers, and nanosilica on the scratch and abrasion resistance of nanocomposite coatings. Ultraviolet (UV) and electron beam (EB) curing were used to cure the nanocomposite coatings. The effect of monomers, prepolymers and nanosilica particles on the viscosity, pendulum hardness, gel content, scratch and abrasion resistance were studied. It was found that the optimum formulation for scratch and abrasion resistance contained 15% Ebecryl 600 epoxy acrylate resin with 30% monomer PETIA and 30% of Aerosil OX-50 nanosilica.

Laser-assisted combinatorial methods for rapid design of wear resistant iron alloys

Combinatorial design methods require the creation of large libraries of materials with varying composition. These libraries are screened for the desired properties, using rapid micro characterization techniques in order to find the most promising compositions for scale-up and final evaluation. These methods are particularly adequate for the systematic scrutiny of complex systems, aiming to find new materials with outstanding properties for particular applications, but they can also be used in the investigation of structure–properties relationships, alloying behaviour studies and phase diagram determination. Up till now, the application of combinatorial methods to the design of tribological materials has been constrained because, since material library preparation is usually carried out by thin film deposition techniques, the sample size is too small for microstructure-dependent properties to be reliably assessed, and no suitable screening tests are available. In the present paper a novel approach to the combinatorial design of abrasion resistant materials, where laser cladding with computer controlled variable powder feed rate is used to synthesize the material libraries and screening is based on microscratching tests is demonstrated. This method was applied to the optimization of the composition of alloys of the Fe–Cr–C system for abrasive wear resistance.

Investigations on Heat Treatment of a High-Speed Steel Roll

High-carbon high-speed steels (HSS) are very abrasion-resistant materials primarily due to their high hardness MC-type carbide and high hardness martensitic matrix. The effects of quenching and tempering treatment on the microstructure, mechanical properties, and abrasion resistance of centrifugal casting high-carbon HSS roll were studied. Different microstructures and mechanical properties were obtained after the quenching and tempering temperatures of HSS roll were changed. With air-cooling and sodium silicate solution cooling, when the austenitizing temperature reaches 1273 K, the metallic matrix all transforms into the martensite. Afterwards, the eutectic carbides dissolve into the metallic matrix and their continuous network distribution changes into the broken network. The second hardening temperature of high-carbon HSS roll is around 793 K. No significant changes in tensile strength and elongation percentage are observed unless the tempering temperature is beyond 753 K. The tensile strength increases obviously and the elongation percentage decreases slightly beyond 753 K. However, the tensile strength decreases and the elongation percentage increases when the tempering temperature exceeds 813 K. When the tempering temperature excels 773 K, the impact toughness has a slight decrease. Tempering at 793-813 K, high-carbon HSS roll presents excellent abrasion resistance.

A nonmineralized approach to abrasion-resistant biomaterials

The tooth-like mouthparts of some animals consist of biomacromolecular scaffolds with few mineral components, making them intriguing paradigms of biostructural materials. In this study, the abrasion resistance of the jaws of one such animal, the bloodworm Glycera dibranchiata, has been evaluated by nanoindentation, nanoscratching, and wear testing. The hardest, stiffest, and most abrasion-resistant materials are found within a thin (<3 microm) surface layer near the jaw tip and a thicker (10-20 microm) subsurface layer, both rich in unmineralized Cu. These results are consistent with the supposition that Cu ions are involved in the formation of intermolecular coordination complexes between proteins, creating a highly cross-linked molecular network. The intervening layer contains aligned atacamite [Cu(2)(OH)(3)Cl] fibers and exhibits hardness and stiffness (transverse to the alignment direction) that are only slightly higher than those of the bulk material but lower than those of the two Cu-rich layers. Furthermore, the atacamite-containing layer is the least abrasion-resistant, by a factor of approximately 3, even relative to the bulk material. These observations are broadly consistent with the behavior of engineering polymer composites with hard fiber or particulate reinforcements. The alignment of fibers parallel to the jaw surface, and the fiber proximity to the surface, are both suggestive of a natural adaptation to enhance bending stiffness and strength rather than to endow the surface regions with enhanced abrasion resistance.