Papers by Keyword: Grinding Performance

Abstract: The paper presents a developed a technology for producing a new abrasive material, which is a refractory ceramic matrix made of aluminum oxide with embedded diamond particles. The tests have shown its advantage over traditional diamond-bearing materials when processing high-hardness ceramics. To synthesize a new material with a predetermined set of operational parameters, it is necessary to build a wear model of a friction pair composed of diamond-bearing ceramic material and ceramics. After analyzing the results of other authors’ studies and assessing the morphology of the contacting surfaces, it is assumed that the contact of microroughnesses on the friction surfaces of abrasive diamond-bearing ceramic tools is linearly elastic. The model is built within the framework of the basic wear equation. The composite material surface was modeled by a set of same radius spherical segments; diamond grains were distributed in the material with a given bulk density. The paper uses the concept of an equivalent surface with the power law distributed of microroughnesses tops. A theoretical relationship is obtained between the micro-and macrocharacteristics of the wear process of a composite ceramic friction pair. The authors established theoretically and confirmed experimentally that the grinding productivity increases with an increase in sliding speed, applied load and diamond grain size. The diamond concentration has no significant effect on the workpiece wear. The established dependencies can help to achieve high productivity of diamond ceramic tools.

Abstract: Any grinding wheel has pores upto 20%. In a grinding situation, when the wheel contacts the workpiece material and grinds, it is literally difficult for the coolant to reach the grinding zone. An attempt is made to create capillary action in the grinding wheel by aligning the pore structure of the wheel and interconnecting the pores-to form a capillary like pore channel. This is done at the grinding wheel fabrication stage at the manufacturer's end.

Abstract: High-efficiency and precision machining of complicated components can be realized by using metal-bonded CBN grinding wheel. However, the difficulty in dressing those superabrasive grinding wheels is one of the main obstructions to popularize its application in industry. Different from the traditional methods, the aim of the paper is to investigate the electro-discharge dressing of bronze-bonded CBN formed grinding wheel. Based on the analysis of electrical discharge parameters and grinding performance, the results show that electro-discharge dressing of CBN formed grinding wheel is feasible. With the increase of pulse duration, pulse voltage and pulse current, the dressing efficiency is increasing, more abrasive grains are protruding, but surface topography of grinding wheel is worsen. Therefore, grinding tests show that, in order to get the dressing quality better and keep the dressing efficiency higher, the bigger electrical discharge parameters are chosen for rough dressing process and the smaller ones are chosen for finishing process.

Abstract: This paper explores effect of rotation speed and media loading on grinding performance of the horizontal stirred mill using the combined method of experiment and simulation on prototype. It selects rotation speed and filling rate to constitute simulation experimental group and conduct the simulation in the EDEM. By studying the effect of rotation speed and medium filling rate respectively on the movement of the medium, the power and the energy utilization,it draw the conclusion of the effect of the rotation speed and medium filling rate on the grinding performance.

Abstract: The paper uses the control variable method, to analysis the effects of rotational speed and media loading on grinding performance on a 230×338 horizontal stirred mill. By comparing the effects of rotational speed and medium filling rate on grinding particle size distribution, the conclusion is that increasing the rotational speed and medium filling rate can get the particle with small and concentration size.

Abstract: The grinding performance of wheel remarkably decreases by the wheel loading in dry grinding of precision hard carbon parts. When the wheel loading occurs, the dressing is carried out to remove loading chips for generation of the grinding performance. However, many abrasive grains, which have enough cutting ability under loading chips, are removed in dressing. We therefore have developed the wheel surface cleaning using adhesive films without dressing to remove loading carbon chips on wheel surfaces in our previous reports, and the cleaning could achieve the lean regeneration of grinding performance of fine grade diamond wheels. The removing ability of loading chips is improved by increasing the peeling speed of adhesive film, the pressing time of adhesive films or the number of pressing time. However the optimum cleaning condition has not been investigated. In this report, from the viewpoint of efficiency in the treatment, we therefore investigate the optimum rolling press process of adhesive film on loading disc wheel surfaces in dry grinding of carbon. The optimum treatment processes are experimentally made clear, analyzing SPa of cleaned wheel surfaces, which is one of surface roughness parameters having the correlation with the protrusion height of abrasive grains. Furthermore, the effect of the treatment on regeneration of grinding performance is experimentally verified by grinding tests of hard carbons.

Abstract: This study was examined about the relationship between the fillers added to the grain layer of a resinoid bond diamond wheel and mechanical properties, the grade, the grinding performance. In the abrasion test using a constant pressure grinding, it was shown clearly that the critical grain holding power changed by kinds of fillers. On the other hand, in the constant cut surface grinding, the grinding interval was evaluated based on the grinding force. And, it was confirmed that the grinding interval changed by kinds of filler. Also, it was found that the characteristics of truing and dressing changed by kinds of filler. In addition, Young's modulus and bending strength of the grain layer of a resinoid bond diamond wheel was measured by three point bending test and ultrasonic pulse method. In the results, it checked that the mechanical properties such as bending strength and Young's modulus of a grain layer changed by kinds of filler. And, the modulus of rupture was calculated from the Young's modulus and bending strength.The result of having compared the modulus of rupture with the critical grain holding power, it was found that the modulus of rupture and the critical grain holding power have good correlation. Namely, the critical grain holding power of a resinoid bond diamond wheel can be evaluated by the modulus of rupture. Furthermore, it was shown that the grinding performance may be able to be predicted by the modulus of rupture of a grain layer of a resinoid bond diamond wheel.

Abstract: The effect of different elements of the auxiliary material on the grinding performance was studied in this paper. Through the grinding experiment, the grinding performance of the abrasive tool can be obtained. It shows that the grinding rate decreased until its content reached to16% following with increasing the NaHCO₃ content. And the abrasive removal rate reduced, while the grinding efficiency was lower than the abrasive tool without adding NaHCO₃. When ZnO content was reached 3%, the grinding rate increased by 43.48% and the grinding efficiency was also improved; while continue to increase its content, the abrasive`s self-sharpening were reduced, which resulting the grinding rate declined. As the NBR (nitrile rubber) content increased, the grinding rate improved and while its content was 20%, the grinding rate increased by 45.93% and the abrasive removal rate reached to the lowest, but the grinding efficiency reduced more. While continue to add NBR, the grinding rate will decrease.

Abstract: In order to solve the problem of the randomly arrangement of the diamond abrasives, a novel orderly arrangement grinding wheel was developed, which used magnetic field to control the magnetic particles to drive diamond abrasives orderly arrangement. Effects of magnetic flux density on magnetic particle distribution was studied. And effects of magnetic particle proportion on magnetic particle distribution was studied. Grinding experiments were carried out on the tungsten carbide YG8 and surface roughness after grinding was also analyzed.

Abstract: Effective cooling and lubricating is got by use a small amount of cutting fluid in MQL grinding. Compare grinding performance under various cooling lubrication, reasonable grinding temperature, lower grinding force, improved surface quality and extended wheel life is got in MQL grinding. The grinding performance of MQL grinding is also influenced by many factors, such as the nozzle shape, position, distance, and MQL flow rate.