Rheological properties of magnetic field-assisted thickening fluid and high-efficiency spherical polishing of ZrO2 ceramics

Abstract

Shear thickening polishing technology using non-Newtonian polishing uid is a low-cost, low-damage polishing method for the ultra-precision machining of complex curved surfaces. However, the shortcomings of traditional shear thickening polishing uid in polishing e ciency and uid viscosity controllability limit its further application., a novel weak magnetic eld-assisted shear thickening polishing uid (WMFA-STPF) containing carbonyl iron particles (CIPs) is presented in this study, which utilizes its weak magnetorheological effect to strengthen the shear thickening phenomenon. The rheological characteristics of the WMFA-STPF samples were investigated. The results show that WMFA-STPF has good uidity in the low shear rate range and better thickening characteristics in the working shear rate range. In order to verify the high e ciency, high quality and high uniformity polishing ability of the weak magnetic eld-assisted shear thickening polishing technology for the spherical surface of zirconia ceramic workpiece, the contrast polishing experiment was designed and nished. The experimental results show that the weak magnetic eld-assisted thickening effect can achieve high e ciency and high quality polishing of hard and brittle ceramics. After 75 min polishing, the surface damage was effectively improved and eliminated, the surface quality and uniformity were greatly improved, and the material removal rate reached 7.82 μm/h, increased by 156%.

Research on prediction method of surface roughness in weak magnetorheological shear thickening fluid polishing

“…The preparation scheme is shown in Table 1. The particles selected for the test sample, the proportion of preparation and the preparation method are all used in the above study [27,28], which will not be described here. The aforementioned rheological properties of WMSTPF at different magnetic field strengths are tested and the results are shown in Figure 3.…”

“…The study proceeded as follows. Based on the weak magnetorheological thickening effect and the study of the magnetorheology shear thickening and polishing method [26][27][28][29][30], a corresponding polishing experimental platform was established and the weak magnetorheological shear thickening polishing fluid (WMSTPF) was prepared. According to the rheological test parameters, a multi-peak fitting method based on Gaussian function was used to establish the constitutive equation, and rheological properties of the medium were compiled and imported by using the function of self-defining material properties.…”

Study on optimization of surface processing technology of silicon nitride bearing ring

“…Using laser local environment of high temperature promoted the hydrolysis of Si 3 N 4 to improve the machining efficiency, Si 3 N 4 materials on the conductive phase, for example, raise its conductivity for wedm processing, this method can obviously materials processing precision and efficiency, but non-contact surface easy to leave after processing method for processing a large number of pits, Surface roughness, surface residual stress, surface fatigue life and other parameters are greatly affected. Literature [12,13] has discussed the Si 3 N 4 chemical assistance processing technology, and compared the removal mechanism of Si 3 N 4 material and the influence of different abrasive types on the surface quality. However, so far, there is still a large space for improvement in the selection of reagents and processing accuracy of chemical assisted processing methods for ceramic materials with different components.…”