Steel writtens guarantee the research of the technology of accurate mirror grinding of hard alloy
- source:BAGANZ CNC Machining
～ of M of 003 μ 0.
The lens face of M of 011 μ , grinding figuration, efficiency is tall, can replace current multistage abrade craft. Keyword: Steel writtens guarantee hard alloy; Online electroanalysis nap grinding; Accurate mirror grinding; Metallic radical exceeds hard abrasive emery wheel to classify date: TG580.
613; Label of document of TG743 piles up: Number of A article: 1004-132 Ⅹ (the problem steel that 2000)03-0288-021 steel writtens guarantee hard alloy exists in grinding writtens guarantee hard alloy is with the tool steel or alloy steel are felt photograph, with carbide of difficult frit metal (basically be WC, TiC) make horniness photograph use the methodological preparation of pulverous metallurgy, its organize a characteristic is ground of imperceptible dispersion of horniness photograph grain distributings in Yu Gang radical. The horniness photograph in alloy basically gifts material is mixed with tall hardness tall wearability, felt photograph gifts again material the function with steel, make steel writtens guarantee hard alloy has the integral performance of steel and hard alloy consequently, make its got applied extensively in each domains. But it is very difficult however that the treatment of its itself is made, especially accurate treatment, because the hardness difference of horniness photograph and felt photograph is bigger,this is, steel radical is excised easily, and hard particle is excised not easily, ju Jijing bead flakes easily from alloy surface come down, form in the surface thereby like having horniness photograph grain the hole of size. The tenacity of steel radical is big at the same time, below pressure of the grinding temperature with be in constant, contact and relative speed condition, the cram that worry bit grinds the stoma between bead, make emery wheel jams quickly workpiece surface produces burn, consequently traditional treatment method obtains low exterior surface roughness very hard, and multistage is abrade efficiency is low, cost is high. Apply online electroanalysis successive nap (ELID) metallic bond exceeds steel of grinding of emery wheel of fine grained diamond to written guarantee hard alloy, exterior surface roughness can amount to 10 Nm left and right sides, and efficiency is tall. This experiment uses technology of ELID mirror grinding to written guarantee to steel hard alloy undertakes nicety is machined, get low surface roughness very easily lens face. The fundamental of technology of grinding of 2 ELID is online electroanalysis nap mirror grinding is a kind of Japanese superprecision that in 20 centuries the development at the beginning of 90 time rises new technology, it is used cast-iron or diamond of iron fiber bond or CBN emery wheel, use electroanalysis the zincous and deliquescent phenomenon in the process, undertake to emery wheel online electroanalysis Xiu Rui grinding, electroanalysis power source uses dc pulse power source, electrolyte employs the aqueous solution of weak electrolyte. Cast-iron emery wheel is positive pole, in electroanalysising, the iron element of emery wheel surface turns Fe2O3 into oxidation film, indispose electrolytic diamond or CBN abrasive protruding stem from emery wheel surface. Grind blunt abrasive to undertake desquamation in time as electrolytic, make emery wheel is in keen condition from beginning to end. The oxidation film that makes at the same time is rising to restrain again electroanalysis the action of process proceed, make emery wheel loss is not sent too fast. After emery wheel surface grinds bead to wear away, oxidation film is gone to by workpiece surface scratch except, electroanalysis process proceed, to nap of proceed of emery wheel surface. This is the process of a loop, avoided emery wheel to pass quick loss already, the grinding position that can hold emery wheel face automatically again [1 ～ 3] , see figure below. Technology of grinding of 3 ELID is opposite sketch map of ELID grinding principle steel writtens guarantee the application of hard alloy 3.
Parameter of equipment of test of 1 experiment condition, experiment sees a table 1, express 2 watches W1 of MM7120 of grinder of 1 test equipment emery wheel.
5 (CIB-D) emery wheel and W1.
5 diamond, CBN mixes abrasive iron radical emery wheel (abstain) HDMD of special power source, Ⅱ ELID mirror grinding is high frequency pulse power source (abstain) HDMY of special grinding fluid, 201 electroanalysis grinding fluid (self-restrained) express rotate speed of main shaft of parameter of grinding of 2 experiments parameter (speed of R/min)1 500 transverse feed (Mm/ .
3 workbench of 1 ～ speed (M/s)0.
05 ～ 0.
08 grinding deepness (Mm)0.
001 ～ 0.
005 electroanalysis parameter voltage (105 electric current of V)90 ～ (3 electrode of A)1 ～ clearance (Mm)0.
1 ～ 0.
2 grinding effect and analysis fall to written guarantee to steel hard alloy undertakes mirror grinding in above condition, ra=0 of workpiece surface surface roughness.
～ of M of 003 μ 0.
M of 011 μ . If use finer emery wheel (W1 above) , can reduce Ra cost apparently, obtain better exterior surface roughness. Analyse gotten grinding result, we discover, workpiece surface surface roughness uses the granuality of emery wheel abrasive and sort to have affinity with place not only, still with grinding fluid deserve to compare have close tie, the grinding fluid of different composition and content, six to one of its chemistry character, the exterior surface roughness that treatment comes out is different. Use HDMY, 110 with HDMY, 200 grinding fluid, we machine an optical glass that reachs lens range, sapphirine, quench the test specimen of the material such as silicon chip of steel, hard alloy, cermet, PCBN, single crystal. But to steel cement hard alloy does not go out with respect to treatment can reach the lens range of 13, convert HDMY of special grinding fluid, 201 mix abrasive with diamond, CBN iron radical emery wheel, in other condition changeless circumstance falls, grind went out to reach lens range (14) steel writtens guarantee hard alloy. Because the composition of grinding fluid and content are right,this basically is electroanalysis the hardness of the speed, speed that become film, ply that become film, film, and be being had by function of organization of treatment workpiece appearance very big impact. In the light of be machined of material different, the composition in adjusting grinding fluid reasonably and deserve to compare, and the sort of abrasive of iron radical emery wheel and granuality, can acquire first-rate grinding position, get lower Ra is worth thereby, achieve the requirement of accurate treatment. 4 conclusion use technology of ELID accurate mirror grinding to written guarantee to steel hard alloy undertakes nicety is machined, attainable surface surface roughness estimates the lens range of class for 10 Nm, the multistage that this method can replace a tradition is abrade the essence that pursue course changes technology, have grinding figuration, efficiency quality of tall, surface is good wait for an advantage, it is a kind of advanced technique that has development outlook very much. CNC Milling