Wear Resistance Of Cast Iron Research Articles

Research of opportunities for adaptation of computer-integrated mixture preparation systems to conditions of foundries in Ukrainian enterprises producing wear-resistant cast iron

The problems associated with the possibility of adaptation of modern computer-integrated control systems for control of imported mixture preparation equipment to the conditions of the foundries in Ukrainian enterprises are considered. It is emphasized that ensuring the given quality of a mixture is an important factor in determining the performance characteristics of wear-resistant cast iron castings. It is shown that the use of modern imported mixture preparation systems suggests the possibility of supplementing by models and algorithms of Ukrainian developments in the synthesis of molding compounds, and optimal control of mixture preparation processes. Proposed options that can complement the QualiMaster AT1/ SandReport/ SandExpert system are a variant of its adaptation to the conditions of foundries of the Ukrainian enterprises. These options are based on mathematical models «mixture composition – mixture properties» in the form of regression equations and algorithms for optimal control of mixture preparation sections. The use of these solutions provides the ability to improve performance, particularly durability of wear-resistant cast iron castings, working in conditions of intensive abrasive friction. This is due to the fact that factor in improving the durability is high quality of working surfaces formed at the «casting surface – molding sand» interface.

Effect of heat treatment on the wear resistance of cast irons

AbstractIn this study, the wear behavior of chilled cast iron and nodular cast iron materials used in camshaft manufacturing has been compared. Nodular cast iron specimens were additionally heat treated at 200 and 300 °C for stress relieving after hardening. Thus, the effect of the stress release treatment on wear behavior was comparatively evaluated with respect to the untreated specimens. The ball-on-disk test described in ASTM G99-05 standard was performed under dry sliding conditions as wear test. The specimens were exposed to dry sliding test under a load of 30 N with a rotational speed of 300 rpm against hardened 100Cr6 counterparts and for the distances of 100, 500 and 1000 m. The results showed two different wear behaviors for the 100 m and 500/1000 m distances, respectively. Under given dry sliding conditions, induction hardened nodular cast iron and slightly stress released specimens exhibited relatively higher wear resistance in the tests over a distance of 500 and 1000 m, while the others showing an increase in wear loss amounts at the same sliding distances.

THE INFLUENCE OF CHEMICAL COMPOSITION OF HIGH-CHROMIUM CAST IRONS ON THE MACHINABILITY

Purpose. This research is aimed to obtain the regression dependence of the machinability on the chemical composition of pig iron (C, Cr, Mn and Ni) in cast state. Methodology. The method of active experiment planning was used to build a mathematical model. Cast irons of composition 1.09…3.91 % С; 11.43…25.57 % Cr; 0.6…5.4 % Mn; 0.19…3.01 % Ni were studied. Cutting tools with plates 10х10 mm out of ВК8 according to State Standard 19051-80 were used for turning. Cutting modes: cutting depth – 0.8 mm, longitudinal feed – 0.15 mm/rot., spindle’s rotation frequency during turning – 200…360 rot./min. Lubricating and cooling liquids were not applied. Evaluation of iron workability was produced by determining the linear tool flank wear per unit length of the cutting path. Findings. Mathematically probabilistic equation of the regression dependence of the cutting tool’s wear on the C, Cr, Mn and Ni content in the machined cast iron were obtained. It was established that with the increase of Cr content in the cast iron to 14.8 % the cutting tool’s wear decreased as a result of formation of carbide eutectic which destroyed the doped ledeburite continuous frame. Further increase of chromium content promoted appearing of chromic carbides with high microhardness which considerably increased the tool’s wear. The conducted research shown that the minimum cutting tool’s wear 0,18 mkm/m was observed during the machining of cast iron containing: 1.09 % C, 14.8 % Cr, 2.3 % Mn and 1.2 % Ni; and the maximum wear is 48,96 mkm/m – when the content was: 3.91 % C, 11.43 % Cr, 5.4 % Mn and 0.19 % Ni. The tool’s wear reached 47.61 mkm/m during the treatment of cast iron containing 3.91 % C, 25.57 % Cr, 5.4 % Mn and 0.19 % Ni. Originality. Mathematically probabilistic model of the dependence of the cutting tool’s wear on the C, Cr, Mn and Ni content in the machined cast iron has been elaborated by the author. Practical value. The model allows optimizing the compositions of wear-resistant cast irons for castings which require the significant mechanical machining. Cast irons compositions were recommended for different exploitation conditions.

Study on diagonal hammer of three kind metals composite casting with block protecting handle

Hammer crusher is widely used in cement, ceramic, mining and electricityother industries, hammer head is one of important parts in crusher, its abrasion performance directly affects the service life of hammer crusher and economic cost. According to bimetalcomposite hammer head is often appear “Hammer handle wear and tear”,“Composite difficult” and the set of casting alloy block hammer head set piece of “come off” phenomenon, which design a set piece type bimetal composite casting straight diagonal hammer, make full use of high chromium cast iron wear resistance and the toughness of low alloy steel. Design a protect block structure reasonably that solve the hammer when the actual production of composite interface is difficult to control and “the problem of hammer head wear” for use. Solve the problem of hammer head wear actively, achieve “energy saving, emission reduction and environmental protection”.

Effect of Carbon Content on Heat Treatment Behavior of Multi-Alloyed White Cast Iron for Abrasive Wear Resistance

Effect of carbon (C) content on heat treatment behavior of multi-alloyed white cast irons with basic alloy composition was investigated. The multi-alloyed white cast irons with varying C content of 1.73–2.34% were prepared. After annealing, the test specimens were austenitized at 1323 and 1373 K, and then hardened by fan air cooling. The hardened specimens were tempered between 673 and 873 K. It was found that the hardness in as-hardened state increased first and then decreased as C content increased. The volume fraction of retained austenite (Vγ) increased with increasing C content. In tempered state, each hardness curve showed secondary hardening due to the precipitation of secondary carbides as well as the transformation of decomposed austenite to martensite during post cooling. The Vγ began to decrease greatly when the tempering temperature was elevated over 723 K. The maximum tempered hardness (HTmax) was obtained in the specimens tempered between 798 K and 823 K where the Vγ ranged from 8 to 12%. The highest value of HTmax was obtained in the 2.00% C specimen hardened from 1373 K austenitizing and in the 2.34% C specimen hardened from 1323 K austenitizing.

Stress analysis of biomass fuel molding machine piston type stamping forming cone

It is established the ram biomass straw machine as the analysis object in this paper,the molding machine cones of stress in the forming process of the analysis of the system. We used pottery instead of Wear-resistant cast iron for improving the performance of forming sleeve. The structure of the forming sleeve was analyzed with the mechanical module of a soft named Pro/engineer in this paper. The result indicated that the program was feasible. With the sensitivity analysis we identified the suitable angle for the sleeve.

Investigation on Microstructure and Wear Resistance of the New CrWMoV High-Alloy Wear Resistant Cast Iron

This paper mainly introduces the new CrWMoV high-alloy wear resistant cast iron prepared by the composition design, the composition proportion and the melting and pouring, and analyses its microstructure and wear resistance. Microstructures and phases of the new CrWMoV high-alloy wear resistant cast iron were analyzed by scanning electron microscopy, energy dispersive spectrometer and X-ray diffract meter. Furthermore, the Rockwell hardness, impact toughness and wear resistance of the material were also studied. The result show that the composition of the new CrWMoV high-alloy wear resistant cast iron is mainly (V, W) C particles which is synthesized in-situ and evenly distributed in the composite, as well as a small amount of (Cr, Fe) 7C3 phase and Fe-Cr phase. The average Rockwell hardness of the composite is about 64.5 HRC, the average impact toughness is 9.85 J/cm2, and the relative wear ability of the composite is about 2 times higher than the Cr15Mo2Cu which shows good wear resistance.

Initial Assessment of Abrasive Wear Resistance of Austempered Cast Iron with Vermicular Graphite

Abstract The work compares the abrasive wear resistance of cast iron containing vermicular graphite, measured in the as-cast state and after austempering carried out at 290°C, 340°C, or 390°C. Theexaminations were performed by means of the T-01M tribological tester using the pin-on-disc configuration. Specimens used for examinations were taken from the end tabs of the tensile specimens, these being cut out of the test walls of the double-leg keel block test castings. Examinations proved that the austempering process increases the abrasive wear resistance of vermicular cast iron by several times as compared with the as-cast material. A tendency for a slight decrease in abrasive wear with an increase in austempering temperature can be stated. The coefficient of friction took a little higher values for cast iron after thermal treatment than for the as-cast material. The work was completed with roughness examination by means of electron scanning microscopy.

Effect of Carbon Content on Heat Treatment Behavior of Multi-alloyed White Cast Iron for Abrasive Wear Resistance

Effect of Carbon Content on Heat Treatment Behavior of Multi-alloyed White Cast Iron for Abrasive Wear Resistance

The Manufacturing of a Special Wear-resistant Cast Iron Used in Automotive Industry

The paper presented here belongs to the researches about the influence of the technological parameters for obtaining a special wear-resistant spheroidal graphite cast iron and his abrasive wear. The studied cast iron had an addition of copper and molybdenum and was elaborated in an induction furnace and the nodular changes were obtained with the “In mold” method. Start from a perlito-feritic structure in the raw state, after applying an isothermal heat treatment, the structure is constituted of inferior binate, residual austenite and marten site with optimal values of abrasive wear and micro-hardness. This material is used for a few automotive components with good results and the abrasive wearing was done on a laboratory plant type.

Structural State, Phase Composition and Mechanical Properties of Wear-Resistant Cast Iron Modified by Ultrafine Powders

The paper explores the effect of a modifier based on ultrafine powders of refractory metal oxides on the change of structural state, phase composition and mechanical properties of cast iron of ИЧХ28Н2 (Russian grade). It was shown that the modifier added to the melt does not change the phase composition of ferrite-austenitic matrix and carbides and is not carbide-forming. Material microstructure changes only due to the presence of a large amount of crystallization nuclei during the casting cooling. It was established that the modification increases the ultimate stress limit by 53%, plasticity by 10.7%, corrosion resistance by 15%, and leads to the reduction of friction factor and linear wear due to the decreasing of structural elements: carbide phase and austenitic-carbidic eutectic.

Local Mechanical Properties of Borides in Fe-B Steels

One of the ways to increase service life of the abrasive wear parts are new developed as-cast steels with ceramic phase. Expensive wear resistant high chromium cast iron can be exchanged by Fe – B alloys. The mechanical properties of the borides in the Fe – B cast iron depend on alloying elements like chromium or nickel. A set of sample with different content of carbon, chromium, nickel and boron has been prepared. Chemical composition (GDOES) and microstructure of the as-cast alloys have been investigated as well as the hardness and Young modulus of the borides. Our results shown that mechanical properties of borides depends both on chromium and carbon content.

Influence of a metal-oxide modifying mixture in ultrafine powder form on the physicochemical characteristics of IChKh28N2 cast iron

Wear-resistant IChKh28N2 cast iron is investigated by X-ray spectral phase analysis and scanning electron microscopy, with and without the introduction of a modifying mixture (d-metal oxides in the form of ultrafine powder and nanopowder) and cryolite (Na3AlF6) reducing agent. The elementary and phase composition is determined; the microstructure of the metal matrix and eutectic is studied. The introduction of a modifying mixture and cryolite reducing agent changes the morphological structure, shifts the ratio of the basic phases, reduces the corrosion rate, and increases the corrosion resistance.

不同介质下激光冲击铸铁材料的磨损性能研究

不同介质下激光冲击铸铁材料的磨损性能研究

Abrasive Wear Resistance of Cast Iron with Precipitates of Spheroidal VC Carbides

Abrasive Wear Resistance of Cast Iron with Precipitates of Spheroidal VC Carbides The paper presents the results of abrasive wear resistance tests carried out on high-vanadium cast iron with spheroidal VC carbides. The cast iron of eutectic composition was subjected to spheroidising treatment using magnesium master alloy. The tribological properties were examined for the base cast iron (W), for the cast iron subjected to spheroidising treatment (S) and for the abrasion-resistant steel (SH). Studies have shown that high-vanadium cast iron with both eutectic carbides and spheroidal carbides has the abrasion resistance twice as high as the abrasion-resistant cast steel. The spheroidisation of VC carbides did not change the abrasion resistance compared to the base high-vanadium grade.

The Effect of Nodular Cast Iron Metal Matrix on the Wear Resistance

The Effect of Nodular Cast Iron Metal Matrix on the Wear Resistance The paper presents results of studies on the effect of the nodular cast iron metal matrix composition on the abrasive and adhesive wear resistance. Nodular cast iron with different metal matrix obtained in the rough state and ADI were tested. To research of abrasive and adhesive wear the pearlitic and bainitic cast iron with carbides and without this component were chosen. The influence of the carbides amount for cast iron wear resistance was examined. It was found, that the highest abrasive and adhesive wear resistance under conditions of dry friction has a nodular cast iron with carbides with upper and lower bainite. Carbides in bainitic and pearlitic cast iron significantly increase the wear resistance in these conditions. In terms of fluid friction the largest wear resistance had cast iron group with the highest hardness.

Technology for improved wear iron

The article describes the results of studies of the effect of carbon, carbon equivalent and titanium on mechanical properties of wear-resistant cast iron. The results of statistical classification, which allows to determine the grade of iron, and a method for assessing the feasibility of additional alloying elements.

Processing and Abrasive Wear Study of Fe-Al<sub>2</sub>O<sub>3</sub>-TiC Composite by Pressureless Ti-Activated Reactive Melt Infiltration

Fe-Al2O3-TiC composite were fabricated by pressureless Ti-activated reactive melt infiltration. In this paper, a kind of Al2O3-Ti porous skeleton was prepared to be infiltrated with Fe-2Cr-3C alloy under vacuum. The microstructure and component analysis was investigated by scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD). Subsequently, the wear testing was conducted to investigate the wear resistance of the Fe-Al2O3-TiC composites. The result show that the Fe-2Cr-3C alloy melt can full infiltrate the two kinds of Al2O3-Ti porous skeleton at 1390°C for 2 h. In the Fe-Al2O3-TiC composite, the coarse Al2O3 particles was surrounded by the TiC layer, which was generated by the Ti-C in-situ reaction in the infiltration process. The abrasive wear resistance of Fe-Al2O3-TiC composite is better than that of the wear resistant cast iron commonly used in industry.

Optica: functional gradient of local properties in ductile iron

Optimisation of local properties of ductile iron castings with a new insert technique has shown to be effective for increasing wear resistance of cast iron. The method is based on an insert technique that allows modification of local properties such as hardness in predetermined locations within a casting. Increased hardness has been obtained both at the surface and within the casting. Locally optimised castings were produced and tested in laboratory and in real use. The effect of bainitic heat treatment, austempered ductile iron (ADI), on hardness of the Optica material is measured and discussed. The effect of ADI treatment on diffusion of alloying elements interacting with carbon from the melt is also discussed. A conventional ultrasonic thickness gauge meter was used to measure the location of the functional gradient material. Transverse rupture strength was measured and compared with unalloyed ductile iron and heat treated castings. Wear tests on trawl hatch shoes showed improved wear resistance of the locally alloyed material. These results are confirmed by laboratory wear tests carried out elsewhere.

Mechanical Performances of Carbonitriding Films on Cast Iron by Plasma Electrolytic Carbonitriding

The plasma electrolytic carbonitriding (PEC/N) process is applied to cast iron using an aqueous solution of acetamide and glycerin as the electrolyte. Mechanical properties of the carbonitriding layers on cast iron are investigated. After the PEC/N treatment, the microhardness and wear resistance of cast iron are improved significantly compared to the untreated substrate. When the substrate is processed at 350 V for 60s, the coating presents the highest microhardness and it is about 554.14HK0.02, and the coating with the highest hardness has the best wear resistance.