Papers by Keyword: Harden

Abstract: On the basis of orthogonal experiment method, the grind-hardening of 65Mn steel had been carried out on a conventional surface grinder with alumina grinding wheel, the influence of depth of cut a_p, table speed v_w, grinding mode g_m, and interaction between depth of cut and table speed av on depth and its uniformity of grind-hardened layer of 65Mn steel were investigated. The results show that, the a_p is the significant factor influences the average depth of grind-hardened layer and the significance ratio of experiment factors from most to least as followed: a_p > v_w > g_m > a_v; the g_m and the v_w are the significant factors influence the depth uniformity of grind-hardened layer and the significance ratio of experiment factors from most to least as followed: g_m > v_w > a_p > a_v. The fairly uniformity of grind-hardened layer with good economy can be obtained when using grinding conditions that the a_p = 0.6mm, the v_w = 0.4m/min, and the g_m =up grinding + down grinding in practical applications.

Abstract: To represent the relation between force and cutting parameters in milling T10 hardened steel, single factor milling experiments with different cutting parameters were done. The experimental result showed that there exited maximum inflection point in force curve under different speeds, and the relation between force and cutting parameters could not be represented with an uniform mathmatical equation. Respective prediction modal of milling force in low speed and high speed were set up using least-square method, which was significant at level of α=0.0005, and its result of R- test was higher than 0.98. This study indicates that the applicable prediction modals in milling T10 steel with low and high speed are different, predict modals being set up can be used to estimate milling force.

Abstract: To compare the effects of different machining parameters on force in milling T10 hardened steel, the features of theoretical forces in up and down milling were analysised, and comparative experiments of milling force were made, whose results showed that the maximum component force in down and up milling was in the direction of radial cutting depth and feed respectively, moreover the maximum force in down milling was significantly greater than in up milling. Further orthogonal experiments of up milling and variance analysis were done, and it was found that the effects of rake angle, velocity, feed, axial cutting depth on milling force were significant at levels of α=0.05~0.0025. This study indicates that selecting milling parameters of up milling, high speed, low feed and axial cutting depth be better. This conclusion can be used as reference in designing milling scheme.