Get together the experiment of optimal grinding speed studies brilliant diamond

08387 grinding experiment produces grinding machine of FC-200D PCD&PCBN special tool in Taiwan aspirant travel. Use model is 40 × of 6A2 150 × the United States of grinding of homebred diamond emery wheel of 15 × 5 W20 M100 is general and electric (the rectangle that GE) company produces (base of knife of 25mm × 5mm)1300 PCD (PCD layer cross section is accumulated for 2.

5mm2) . Use Japan to produce Mitutoyo number to show micrometer (precision 0.

001mm) measures PCD knife base grind except length; Fixed position piece is installed on grinder feed system, use feed number to show a system (precision 0.

001mm) measures the thickness of wear and tear of diamond emery wheel, beg a PCD material to grind respectively through computation compare except rate of rate, emery wheel wear and tear and wear and tear. Water radical cooling fluid is used in the experiment, grinding craft parameter sees on watch. In grinding process, with Kistler synchronism of the appearance that measure power measures grinding power. Produce the Japan of park of PCD test specimen after grinding the observation on lens of JSL-5600LV scanning report its are microcosmic form appearance. 3 tests result and analytic graph 1 PCD grind the concern plan that eliminates comparing of rate, wear and tear and grinding rate the microcosmic form appearance of surface of grinding of the PCD when grinding of 2 low speed pursues the microcosmic form appearance of surface of grinding of the PCD when grinding of 3 high speed pursues the relation of rate of wear and tear of 4 emery wheel and grinding speed pursues. See by the graph, PCD is ground rise except what lead Q to follow grinding speed Vs and increase by degrees; Wear and tear is put in hump than G curve, namely middling speed grinding (value of the G when 14m/s) of ≤ of 7m/s ≤ Vs is the greatest, and the G when grinding of tall, low speed is worth all lesser. The reason that the author thinks to produce this one result is as grinding speed rise, of the grinding mechanism of PCD and diamond emery wheel wear away the form produced metabolic be caused by. The grinding mechanism of PCD basically has kind of 4 kinds of purify: Purify of the purify of concussion brittleness purify, brittleness of edge brilliant exhaustion, fatigue brittleness that nod corrode, thermochemistry and machinery heat up purify. Concussion brittleness purify basically happens in grind bead to be cut place (namely point is in) , all can happen below any grinding speed; And other purify means issues position of its primary and secondary to be able to produce change in different grinding speed. As grinding speed rise, grinding area temperature will lift gradually, by the physics of PCD, chemical function knowable, what thermochemistry and mechanical hot purify occupy scale to will increase gradually in grinding. Graph 2, graph 3 be in for test sample respectively low speed (Vs=3.

92m/s) and high speed (Vs=25.

The grinding surface when 17m/s) grinding is microcosmic form appearance. By the graph 2 visible, the indentation that size of diamond surface existence reachs to differ near brilliant of edge of PCD grinding surface reachs freely stagger micro-crack, and grinding surface did not see apparent flowing area and mechanical nick. Means of purify of material of the PCD when this shows low speed grinding reachs purify of the fatigue brittleness that nod corrode to give priority to with purify of edge brilliant brittleness, it is with local thermochemistry and mechanical hot purify complementary. By the graph 3 visible, PCD grinding surface is put in a lot of flowing areas, apparent mechanical nick is seen on flowing area, and its go up basic the nonexistent hole that nod corrode and micro-crack; In the meantime, in the indentation that PCD grinding surface reachs diamond grain surface to still be put in size to differ near brilliant of edge of low-lying place, PCD. The purify means of material of the PCD when this shows high speed grinding heats up purify and purify of brittleness of edge brilliant exhaustion to give priority to with thermochemistry and machinery, it is with purify of the fatigue brittleness that nod corrode complementary, this and the viewpoint photograph be identical of concerned document. Accordingly, as grinding speed rise, although odd ply reduces a cutting that wears bead, but produced change because of PCD grinding mechanism, make PCD is ground instead rise except what lead Q to follow grinding speed Vs and increase by degrees, but because of wearing bead wear away normally also at the same time aggravate, range of Q value growth is not so big. PCD wear and tear is in than G curve middling speed (hump of the existence inside limits of grinding of 15m/s) of ≤ of 7m/s ≤ Vs. The author thinks this is to grind bead to wear away be caused by of formal happening change. The graph shows the emery wheel wear and tear that is correspondence 4 times to lead the relation curve of Qs and grinding speed Vs. By the graph knowable, inside the grinding speed limits of hump of corresponding G curve, the rate of wear and tear of emery wheel is the minorrest; And the wear and tear that issues emery wheel in other grinding speed is led all bigger. By the graph 5 are shown tangential the relation of grinding force Ft and grinding speed Vs is knowable, in grinding process, tangential grinding force Ft follows grinding speed Vs rise and reduce. When low speed grinding, action at sheet the Ft that grinds bead to go up is bigger, grind the whole with an easy premature generation to fall off wear away, rate of emery wheel wear and tear is accordingly older; When middling speed grinding, action at sheet the Ft that grinds bead to go up is reduced, and grinding area temperature is not quite high, because this grinds bead to produce premature whole not easily to fall off,had reached fast hot passivation to wear away, however with small broken wear away give priority to, grind bead to be in optimal job status, rate of emery wheel wear and tear is the accordingly minorrest; When high speed grinding, although action at sheet the Ft that grinds bead to go up is reduced further, but because grinding rate is high and bring about grinding area temperature to lift, because this grinds bead to will produced fast hot passivation wear away, make grind bead to lose grinding ability very quickly, bring about rate of emery wheel wear and tear to increase quickly. Wear away as a result of what wear bead form as grinding speed rise and produce afore-mentioned change, and PCD is ground except rate rise and increase what follow grinding rate, accordingly, inside the grinding speed limits that grinds bead to be in optimal job status, the wear and tear of PCD material is the biggest than G, namely hump of existence of curve of comparing of wear and tear. In grinding process, by the graph 5 show a way the relation to grinding force Fn and grinding speed Vs is knowable, in low speed grinding (when Vs ≤ 15m/s) , fn follows grinding speed to rise and increase of Vs; High speed grinding (when Vs>15m/s) , fn follows the accretion of Vs and reduce. Although this and conventional grinding force and grinding velocity relationship not agree with, but the verdict that PCD grinding mechanism rises along with grinding speed and produces afore-mentioned change can make a person be convinced ground explains result of this one test. Well-known, below regular job requirement, the passivation of bead of stone mill of the King Kong in emery wheel wears away to rise and increase what degree follows Vs; In other grinding condition identical premise falls, grinding area temperature follows grinding speed Vs rise and lift. When low speed grinding, means of PCD material purify nods corrode brittleness purify to give priority to with purify of edge brilliant brittleness and exhaustion, it is with local thermochemistry and mechanical hot purify complementary, the average temperature of grinding area is inferior, the hardness of PCD surface follows temperature (speed) elevatory and the scope that reduce is very little, and the passivation of bead of stone mill of the King Kong in emery wheel wears away to rise and increase what degree follows Vs, accordingly, rise and increase what the Fn when low speed grinding follows Vs; When high speed grinding, means of PCD material purify heats up purify and purify of brittleness of edge brilliant exhaustion to give priority to with thermochemistry and machinery, it is with purify of the fatigue brittleness that nod corrode complementary, the average temperature of grinding area is higher, the hardness of PCD surface follows temperature (speed) lift and reduce apparently, accordingly, the Fn when high speed grinding follows Vs rise and reduce. The place on put together is narrated, when material of PCD of the grinding below the requirement that imposing cooling fluid with diamond emery wheel, grind to material compare G except rate Q and wear and tear function of these two targets, inside limits of middling speed grinding, g value is the greatest, q value is greater also, emery wheel is in optimal job status. Vs of speed of the grinding when this makes clear grinding PCD material is put in an optimal limits. 4 conclusion as grinding speed Vs rise, the purify mechanism of PCD material will produce change, control PCD material purify by brittleness purify namely to heat up purify to control change of PCD material purify at the same time by brittleness purify, thermochemistry and machinery, and as Vs rise, thermochemistry and place of mechanical hot purify occupy specific gravity to increase gradually. As grinding speed Vs rise, PCD material is ground increase gradually except rate Q, but growth range is lesser. Mix than G to PCD material wear and tear grind except rate Q, put in limits of speed of an optimal grinding. Inside this limits, g value is the greatest, q value is greater also, value of Qs of rate of emery wheel wear and tear is the least, namely emery wheel is in optimal job status. In the article experiment condition falls, limits of optimal grinding speed is: 14m/s of ≤ of 7m/s ≤ Vs. When low speed grinding, the law follows grinding speed to rise and increase of Vs to grinding force Fn; When high speed grinding, fn follows Vs rise and reduce. Tangential grinding force Ft follows grinding speed Vs rise and reduce. CNC Milling CNC Machining