Grain of SiC of treatment of PCD cutting tool enhances aluminium radical the reasonable cutting speed of composite material
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Base On The Test Of PCD Tool Cutting High Strength SiCp Reinforced Aluminum Matrix Composite, the Influence Of Cutting Speed On Cutting Force, surface Roughness, tool Life And The Cutting Length Were Discussed, and The Optimum Cutting Speed In This Course Was Summarized.
It Is Shown That The Best Total Efficiency Can Be Obtained When The Optimum Velocity Is From 30 To 40 Meters Per Minute.
The development of preface of Cutting Performance1 of of Cutting Speed of of Diamond Tool of of Keywords Polycrystalline as aerospace technology, qualitative to material light quantify, the demand of high strenth rises increasingly. Grain of tall stiffness, high strenth enhances aluminium radical the light-duty alloy material that composite material is the performance of can contented special physics that a kind of new development gives and requirement, it has high intensity, stiffness and admirable high temperature mechanical function, but SiC part is contained in material bigger, wear away to cutting tool have bigger effect, the cutting tool that gives priority to with high-speed steel and hard alloy material exposes the point that gives inadequacy in cutting time beneficial. Diamond and other data are compared, all have the superior performance that cannot compare in hardness, coefficient of thermal conductivity, hot coefficient of expansion and respect of coefficient of friction. The 1/50 ～ 1/800 that diamond and the attrition quantity that conjugate of all sorts of metal stuff, metalloid material chafes are hard alloy test specimen only [1] . Extremely low coefficient of friction can reduce cutting force and deflection not only, and not easy when cutting generation accumulates bits tumour, can acquire good treatment surface quality thereby. PCD (much brilliant diamond) cutting tool is burgeoning exceed material of strong cutting tool, by the making synthetic diamond that passes concentration microcrystalline body issues agglomeration in high temperature high pressure and become. The as a result of additive affiliation in agglomeration process, make the formation between diamond crystal is mixed with TiC, SiC, Fe, Co the Ni combinative bridge that is bases, in the firm framework that diamond crystal forms at combining the bridge with the combinative form of covalent bond is embedded firmly, make the hardness of PCD and tenacity rise greatly, so PCD knife has the tall hardness of diamond, tenacity is taller than single crystal diamond however, bit matrix has high bending strength again. Undertake with compound diamond razor blade turning is machined, for carborundum composite material finish machining puts forward aluminium radical a kind of new efficient treatment method [2, 3] . The article reachs the influence of cutting tool life to temperature of cutting force, cutting through inspecting cutting speed, summary gives PCD cutting tool to be opposite cutting is existing in process of this kind of material reasonable cutting speed limits. Test of 2 experiments means is on CKM6132 nicety lathe undertake. Kistler was used to measure what oscillograph of amplifier of charge of power instrument, Kistler and SC16 light comprises to survey power system when measuring power. The test specimen that experiment place uses is used for spaceflight make, its material is mechanical performance data sees a table 1. The thick grain PCD that experiment cutting tool produces with American global company is compound piece make, its geometry parameter and mechanical performance data see a table respectively 2 with the watch 3 [2] . Express 1 carborundum aluminium radical the hardness of G/cm3 of density of Mechanical Properties Of SiCp/Al Composites of of Table 1 of mechanical performance data of composite material MPa2 of bending strength of MPa of compressive strength of HB tensile strength MPa.
Radius of circular arc of point of a knife of tool cutting edge angle of the horn after the horn before the Geometrical Properties Of PCD Tools of 7613731747095800 of geometrical parameter Table 2 that express cutting tool of 2 PCD - 6 ° of 6 ° 70 ° 0.
GPa of quantity of stretch model of MPa of compressive strength of bending strength MPa heats up the HV of hardness of Mechanical Parameters Of PCD Tools of of Table 3 of mechanical performance data that 1mm expresses cutting tool of 3 PCD W/m of coefficient of thermal conductivity of C of ° of 10-6/ of coefficient of expansion. K6500~8000280042005601.
2~4.
5100~109 experiments to undertake on CKM6132 nicety lathe. Kistler was used to measure what oscillograph of amplifier of charge of power instrument, Kistler and SC16 light comprises to survey power system when measuring power. 3 cutting speed is aluminous to machining carborundum base the influence of composite material 3.
1 cutting speed pursues to the influence of cutting force the relation curve between speed of the 1 cutting when regarding cutting as fluid to use emulsion and static force (feed F=0.
12mm/r, cutting deepness A=0.
10mm) . Can see from inside the graph, 3 to Fy of cutting component of force, fx and Fz all increase along with the accretion of cutting speed V, and Fy is more than Fx and Fz far, this and metallic cutting circumstance are disparate, appear this kind of circumstance, because this composite material contains the SiC of higher class status,think commonly, have extremely tall hardness be caused by. Additional, the compressive strength of this composite material is more than tensile strength to also bring about Fy far be more than other twice component of force. In cutting process generation collapse breaks cutting, and concentration is near cutting tool, cutting and before the osculatory area of knife face is small, attrition force is lesser, the means of cutting purify is brittleness rupture, these elements bring about Fz lesser. Graph the influence of 1 cutting speed to static force Fig.
The addition of of 1 Influence Of Cutting Speed On Cutting Static Force as cutting speed, the rate of meet an emergency of material increases, the cutting bulk inside unit time increases, bring about cutting force to increase along with the accretion of cutting speed. The graph shows cutting rate 2 times aluminous to cutting carborundum base the influence of dynamic force amplitude when composite material, see from inside the graph, cutting carborundum is aluminous base when composite material, oscillatory phenomenon is very apparent, because Fy is the main factor that affects vibration,this is, when cutting composite material, fy ambitious at other two component of force, bring about a system to produce vibration thereby. Carborundum is aluminous base the hardness profile in composite material is inhomogenous, in the aggravate on certain level oscillatory. Graph the influence of 2 cutting speed to dynamic force Fig.
2 Influence Of Cutting Speed On Cutting Dynamic Force3.
Result of test of 2 cutting temperature reachs analytic M. Lee [4] studying carborundum of cutting of PCD cutting tool is aluminous base of composite material wear away the discovery when mechanism, the hardness of PCD cutting tool lifts along with temperature and reduce, when temperature arrives at 700 ℃ , PCD begins graphitization, hardness drops quickly, cutting tool invalidation, accordingly, composite material cutting must control cutting temperature strictly. Generally speaking, cutting speed is the influencing factor with cutting the mainest temperature. In process of composite material cutting, as cutting speed rise, cutting temperature is apparently elevatory, discovery is returned in the experiment, when cutting speed is more than 40m/min, cutting temperature achieves 500 ℃ , cutting tool wears away aggravate, already cannot continue again cutting, because what measure temperature to be the temperature that is apart from above of 2mm of point of a knife,this is, when measurement point temperature achieves 500 ℃ , the temperature of point of a knife already achieved 700 ℃ , PCD already began graphitization, cutting carborundum is so aluminous base speed of the cutting when composite material cannot be more than 40m/min. 3.
The influence of 3 cutting speed to cutting tool durability cutting speed all along is the factor with the mainest durability of influence cutting tool, cutting carborundum is aluminous base composite material is not exceptional also, from the graph 3 can see, in double logarithm coordinate, v-T shows linear concern inside limits of V=30 ～ 50m/min, and in low speed (20m/min) reach high speed (96m/min) when all do not satisfy this rule, rate of the cutting when this and cutting metal is similar to the influence rule of cutting tool durability. See from inside the graph, cutting tool life as cutting speed elevatory and quick drop. Cutting tool wears away to basically behave the little grain that goes up for point to fall off first in right-hand seat of cutting strength effect, appear around point scraggly desquamation trace, form cutting tool point to wear away. Get radial cutting power as a result of place of the cutting tool when turning carborundum composite material bigger, more carborundum horniness look exists again in carborundum composite material, both and joint action is caused wear away at the back of cutting tool. Cutting tool wears away to become blunt to certain level point, cutting force leap, continue cutting, die occurrence point of a knife blade, bring about cutting tool finally to discard as useless. Graph the influence of 3 cutting speed to cutting tool durability Fig.
of 3 Influence Of Cutting Speed On Tool Life pursues 4 with the graph the 5 around after showing 2min of cutting of cutting tool of the PCD when going out to be 50m/min in cutting speed respectively the face wears away the photograph of scanning report lens of configuration, show cutting tool already happened to flake badly wear away. Pass afore-mentioned analysises, use tall silicon of cutting of PCD cutting tool aluminium radical recommends the cutting career that chooses left and right sides of 30 ～ 40m/min when composite material. Graph before 4 cutting tool wear away configuration × 50Fig.
4 Wear Appearance In The Face pursues at the back of 5 cutting tool wear away configuration × 50Fig.
The logical choice of speed of cutting of 5 Wear Appearance In The Flank4 passes afore-mentioned analysises knowable, treatment carborundum is aluminous base the cutting speed existence of composite material is optimal limits. Under or prep above this limits, the life of cutting tool can be reduced quickly, inferior cutting speed still can bring about exterior surface roughness to increase, the graph is shown 6 times be the same as cutting length for cutting speed (L) and cutting tool durability (the relation of T) . Can see from which, when V=30 ～ 40m/min, cutting length is the longest, cutting tool life is taller also. Static state and dynamic force amplitude are right now inferior also. Although be below this speed,cutting efficiency is not very tall, but surface roughness of length of cutting tool cost, cutting, surface and cutting force all be in relatively beautiful condition. When because this uses carborundum of cutting of PCD cutting tool,aluminous base material expects, limits of commendatory reasonable cutting speed is 30 ～ 40m/min. Graph the relationship of 6 cutting velocity to durability of cutting length, cutting tool Fig.
of conclusion of 6 Influence Of Cutting Speed On Cutting Tool Life And The Cutting Length5 (1) in cutting Gao Gui aluminium radical when composite material, as V rise, static cutting force increases, fz of ＞ of Fy Fx. Oscillatory phenomenon is more apparent, cutting temperature is elevatory, cutting tool wears away aggravate, affect cutting tool life badly. (2) PCD cutting tool is in aluminium radical puts cutting carborundum in reasonable cutting speed limits when composite material, inferior or higher cutting rate can reduce cutting tool durability significantly, recommend use cut speed limits in all these of 30 ～ 40m/min about, inside this limits each function index is in relatively beautiful condition. CNC Milling