The experiment that bits form appearance cuts in paper-thin turning is analysed

5 Mm. Control of the temperature inside the lab is in (℃ of 20 ± 1) , collect to facilitate cut bits, did not use cutting liquid. Graph the picture of SEM of integral form appearance that 2 aluminium cut bits pursues 3 cut bits relatively featheredge SEM photograph pursues 4 cut bits relatively the LY12 aluminium that the aluminous capable person that laboratory of webbing SEM photograph employs is diametical 90mm is marvellous. The cutting deepness that turning place uses is 3 μ M; Feed is 1.

8 μ M/r, main shaft rotate speed is 1200r/min. Graph the 2 SEM photographs that are appearance of gets form of the whole that cut bits. This is relatively typical successive and banding cut bits, actual measurement cuts bits width to be 65 μ M about, criterion by type (ply of attainable the smallest cutting is 4) 36 Nm. Graph 3 with the graph the photographs of 4 local enlarge SEM that are the featheredge that cuts bits and webbing respectively. Can see by the layer shape chip that cuts slippage accumulation forms cut bits apparently from which. When cutting ply is bigger, the construction that cut bits is tighter; When cutting ply decrescent, the structure that cut bits is more loose. To the graph 4 in can measure those who get correspondence of place of ply of the smallest cutting to cut bits ply, it is 860 Nm about. Union by type (the Acmin of ply of the smallest cutting that 4) gets is 36 Nm, discover the right now ply that cut bits is 24 times of cutting ply about, cut bits mediumly to be out of shape at groovy cutting greatly far coefficient. Because right now the point radius of diamond lathe tool has been in same amount class with cutting ply,this is, had exceeded cutting ply even, actual cutting process is like a cylinder to undertake sliding squashing in workpiece surface same, can make cut horn to become very small. When this explains when cutting ply reduces accept rice level, cut bits to be out of shape will increase significantly. Single crystal germanium is material of a kind of brittleness, in the cutting experiment to it, still be used and the identical lathe tool in test of turning aluminous aptitude. Choose bigger feed (when M) of μ of 3 ～ 5, cut bits to break for collapse graininess break bits, form dirt mist to float in air. When feed is reduced, can discover successive zonal cuts bits. Cutting deepness is 2.

5 μ M, feed is 1.

0 μ M/r, the picture cutting bits that when main shaft rotate speed is 2500r/min, gets sees a picture 5. Cut bits width actually by the graph 5 can get, it is 60 μ M about. By type (4) can get ply of the smallest cutting is 19 Nm about. This should be less than those who use same lathe tool to undertake to aluminium turning gets ply of the smallest cutting, because aluminium is plasticity material,the likelihood is, in generation of the meeting below lathe tool action bigger flexibility is out of shape, when cutting ply very hour, excise hard; And single crystal germanium is brittleness material, flexibility is out of shape dinky, be in so cutting ply very the hour still can be excised. Graph germanium of 5 single crystal cuts photograph of SEM of appearance of bits whole form to pursue germanium of 6 single crystal cuts bits local SEM photograph pursues the 6 local SEM pictures that cut bits for single crystal germanium. Because single crystal germanium is semiconductor material, it is very difficult to should be in next bigger enlarge is diploid observing to cut bits form appearance with SEM microscope so. Can see from inside the graph, the ply that cuts bits is 400 Nm left and right sides about, this and cut bits to be out of shape to what aluminium undertakes turning agree basically. Think at present, change of fragile to existing in brittleness material turning model is nodded, when cutting ply is less than critical cutting ply, material will be out of shape with cutting slippage plasticity means purify; When cutting ply is more than critical cutting ply, material will produce brittleness to destroy, this will affect exterior quality severely. From the graph 5 with the graph 6 in discovery, although cut the whole of bits to show successive and banding, but also exist among them a few pit that because brittleness is destroyed,cause are nodded. These hole drops cause by two parts: When feed of this second lathe tool, the brittleness that in cutting ply larger part produces is destroyed; As a result of the destruction of generation hole site has certain depth, hole arises to nod the influence with was caused certain to this second feed turning on circular arc face when before a few feed. Accordingly, will look from the photograph that cut bits, destroy what hole nods to distributing appear desultorily. The relation between the deepness that nods generation to destroying hole and cutting ply still remains to study further. 3 conclusion author uses lathe tool of diamond of circular arc blade to have turning test to germanium of aluminous, single crystal, the accept rice level that achieved pair of plasticity material and brittleness material is scanty cutting. In exceeding accurate turning process, when cutting ply reachs accept rice level, as a result of the effect that the point radius of diamond lathe tool causes, cut bits be out of shape coefficient is more than what convention falls to cut bits to be out of shape far coefficient, can amount to 20 above commonly. In because this is in,exceeding accurate turning, to get exceeding slick surface, the point radius of diamond lathe tool should be controlled strictly, should choose the lathe tool with better point. What the ply of the smallest cutting that gets in the cutting experiment to germanium of brittleness material single crystal wants to be less than aluminium of plasticity material metal is the smallest cut thick. This is the flexibility that can arise because of brittleness material is out of shape dinky, be in so cutting ply very hour, still can excise. In single crystal germanium cut the hole place that there is a few to destroy generation as a result of brittleness on bits, if these hole sites expand,already machined the surface, will affect exterior quality badly. The relation between the deepness that nods generation to destroying hole and cutting ply still remains to study further. CNC Milling CNC Machining