New-style nickel experiment of alloy grinding function studies Jigaowen

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Alloy of 1 foreword high temperature is much group yuan complex alloy, have good high temperature strength and thermal stability, in 600 ~ the oxidation of 1100 ℃ leaves can long-term job with burn-in condition burning gas, be applied extensively in aviation, space navigation, shipping and chemical industry consequently. The component of general high temperature alloy in industrial production is iron radical, nickel radical and cobalt base 3 kinds, the Л of the Ж that it is В that the article studies 1 model (the following logogram is this code name) alloy of nickel radical high temperature. Because high temperature alloy serves as crucial parts of an apparatus to leave long-term job in high temperature and complex stress condition normally, to acquire good property, need to add normally in machining a process all sorts of elements and use aggrandizement technology, make the cutting of high temperature alloy (grinding) processability can be poorer, basically reflect in: When alloy of grinding high temperature, emery wheel grinds bead to more serious wear and tear wears away to jam with conglutinate, grinding comparing is very low (the grinding of common emery wheel compares G=1 ~ 2) ; Because alloying element of high melting point is contained in material of alloy of nickel radical high temperature, have the compound between carbide photograph and metal G" photograph and G photograph, the plasticity with easy strong generation is out of shape, consequently grinding force is gotten greatly than general steel makings much; Because the thermal conductance of high temperature alloy is very low, the per cent of quantity of heat that workpiece passes into when grinding consequently is inferior, and quantity of heat expresses facing in paper-thin grinding centrally, make grinding temperature very high; Fall in the integrated action of grinding force and temperature, produce grinding burn, exterior quality assures not easily. В Ж Л 1 a kind be development of group of engine of Shenyang dawn aviation new-style cast alloy of nickel radical high temperature, the processability in actual production can be poorer, the treatment efficiency that manufactures to increase large quantities of amounts and quality, reduce cost, study its grinding processability can have very important sense. Л of Ж of 2 В the chemical composition of 1 and Л of Ж of mechanical function В the component of 1 is complex, basically be nickel (60%) agreement ≥ and Cr, W, Mo, Ti.

, a few kinds of elements such as Al, C, to share of group of a few minim (for example S, P, Mn, Si) have strict control, make its have good high temperature strength and thermal stability, normal temperature issues 670MPa of ≥ of tensile strength Sb, hardness of cloth family name is 300 ~ 600. The content of component of 1 each composition sees В Ж Л watch 1. 1 alloy content comprises Л of Ж of the В that express 1, content of % elements C Cr W Mo Ti Al Ni Fe B Si S P 0.

10-0.

17 15.

0-17.

0 2.

0-2.

5 3.

5-5.

0 2.

0-3.

0 2.

0-2.

8 base ≤ 3.

5 ≤ 0.

13 ≤ 2.

0 ≤ 0.

02 ≤ 0.

1 grinding of Л of Ж of 023 В the test specimen of experimental test condition of function: 43.

25 × of 5 × 240mm cast; Size of experimental grinding area: Grinding length L=43.

5mm, polishing width B=10.

0mm; Machine equipment: Hydraulic pressure is all-purpose MYA6025 of tool grinding machine, inside MD215 of round tool grinding machine. Wear a stuff: Plane abrasion 32 × of 125 × emery wheel of 15 granuality 100#CBN (chroma 100%) , 32 × of 125 × emery wheel of 15 granuality 180#CBN (chroma 100%) , 32 × of 125 × emery wheel of Bai Gangyu of 15 granuality 80# ; The circle grinds emery wheel of F10 granuality 120#CBN inside, emery wheel of F10 granuality 180#CBN (chroma 100%) . Test instrument uses Kistler to suppress report 3 measure power instrument 9257B to trends, kistler charge amplifier 5007, data sampling system uses card of 12 A/D interface, 486 personal computer, data collects processing software system. In experiment of orthogonality of experimental program grinding, according to 2 elements program of test of 3 levels orthogonality (2) seeing a table undertakes grinding with 180#CBN emery wheel. Express experiment of 2 grinding orthogonality and Frmm Vsm/s FtN FnN 1 0 of prolific check date.

01 17.

52 17.

45 27.

21 2 0.

01 25.

96 12.

60 23.

22 3 0.

01 32.

45 7.

97 15.

64 4 0.

02 17.

52 30.

02 45.

56 5 0.

02 25.

96 23.

05 39.

46 6 0.

02 32.

45 15.

72 25.

74 7 0.

03 17.

52 42.

69 62.

30 8 0.

03 25.

96 33.

84 55.

45 9 0.

03 32.

45 25.

92 44.

49 grinding force follows plan of experiment of grinding process change, emery wheel of the WA 80# that passes with new nap respectively, CBN 100# , CBN 180# has a test, record grinding strength of the experiment. Means: Go against grind, experimental frequency: 80 ~ 100, parameter: Vs=25.

8m/s, fr=0.

01mm, VW=0.

67m/min. Nap plan, undertake Xiu Yuan first, use method of diamond pen nap. Parameter of nap of white corundum emery wheel is: Thick repair Vs=25.

8m/s, fr=0.

02mm, fa=1mm/s, 2; Essence of life repairs Vs=25.

8m/s, fr=0.

01mm, fa=1mm/s, 2; Light repairs Vs=25.

8m/s, fr=0mm, fa=1mm/s, 2; The nap plan of CBN emery wheel is: Essence of life repairs Vs=25.

96m/s, fr=0.

01mm, fa=1mm/s, 4; Light repairs Vs=25.

96m/s, fr=0mm, fa=1mm/s, 2. Of the CBN120# that experiment of round grinding craft uses external diameter to be F10 respectively inside and CBN180# inside the test specimen that the circle grinds the aperture inside arenaceous wheel pair to be F10 has grinding craft test, the rotate speed of grinding emery wheel is 24000r/min, add cutting juice, determine surface roughness undertakes comparing is opposite, examine next treatment quality, regard the application in actual production as the basis. Formula of grinding strength experience can get through using orthogonal experiment and multivariate and linear analysis formula of grinding strength experience is Ft=104.

32Fr0.

924Vs-1.

003Fn=104.

00Fr0.

823Vs-0.

The unit of the Ft in 741 type, Fn is N, the unit of Fr is Mm, the unit of Vs is Mm/s. Accept the restriction of experimental condition, the floating rate platform secures the ≈ that it is VW 0.

67m/min. Pursue 1 feed is tangential to grinding the influence sketch map of force pursues 2 feed pursue to the influence sketch map of grinding radial load the change that force of the grinding when grinding of 3 Bai Gangyu emery wheel follows grinding course pursues the change that force of the 4 grinding when using CBN100# abrasive follows grinding course pursues, with Л of Ж of В of CBN 180# grinding in the process of 1, grinding power is not great, it increases along with the accretion of feed Fr, apparent along with the accretion of speed of emery wheel grinding reduce, because this feed is right grinding power influence is very remarkable. Metabolic process curve is like the process of grinding force change when the result that grinding force changes along with grinding process analyses Bai Gangyu to undertake grinding is machined the graph is shown 3 times. The trend line that is Ft and Fn with the curve of Ft, Fn is accompanied respectively in the graph. In the process that has machining with corundum emery wheel, grinding force increases all the time, accompany in all grinding process have more serious conglutinate appearance, be equivalent to wearing away the emery wheel of passivation is when grinding, can grind the desquamation of bead because of the part sometimes and make grinding force drops inside a paragraph of period, be enclothed basically by grinding material to the surface of final phase emery wheel, cause the metal of conglutinate and contact of surface of the spare parts that be ground, accordingly the force of Fn direction adds quickly, and because the force of Ft direction became sliding friction, change is not so big. Although use force of the grinding when grinding of corundum emery wheel to increase ceaselessly, but be in 80 times grinding power is not great before, material of demonstrative corundum emery wheel falls in the circumstance of a few grinding still is sharper, efficiency is taller, but use not easily in many grinding circumstance. The curve of the metabolic change process of force of the grinding when CBN 100# grinding is machined is shown 4 times like the graph, the trend line that is Ft and Fn with the curve of Ft, Fn is accompanied respectively in the graph. See by the graph, when the emery wheel grinding that passes with firm nap, earlier grinding force is relatively lesser, subsequently grinding force is added quickly to maximum, after achieving certain grinding power, continue again grinding, grinding force has fixed rate again reduce, reach a longer stable level. Machining complex flexibility is out of shape the emery wheel surface that makes Dao Jigang has been repaired falls off easily, grinding force is reduced, actual grinding deepness increases. Because emery wheel surface grinds bead to count basic already stability, grind a rapid passivation, increase to exceed binder to reach ceaselessly when grinding force wear bead can when susceptive degree, grind bead to begin to fall off, those who make participate in grinding is effective the number that wear bead decreases, consequently grinding force has the fall of certain level again, in fall begin to reach steady state after certain level, the time that steady state begins is 20 ~ 30 times about. The steady state of CBN emery wheel is longer, the wearability that shows CBN emery wheel is better, grind bead not easy blunt. The change of force of the grinding when grinding is machined is shown 5 times like the graph, the line is accompanied to be the trend line of Ft, Fn likewise in the curve of metabolic process. See by the graph, the grinding process change when using grinding of CBN180# emery wheel and CBN100# grinding process are basic and same. Different is, force of grinding of CBN180# emery wheel wants small much, this basically is grinding bead is ground to fall off more easily in the process, make the number wearing bead that shares grinding decreases, grinding force is accordingly small. The grinding of emery wheel and wear away the exterior state of state emery wheel accompanies certain conglutinate in the process of alloy of grinding high temperature. The conglutinate of corundum abrasive is relatively serious, the reason is when using corundum grinding, such as Cr2O3, Al2O3 all belong to 6 systems, have A-Al2O3 structure, close of its lattice parameter, can make form stronger conglutinate Al, Cr, Ti through its surface oxide and corundum, want to use alloy of corundum grinding high temperature only, no matter adopt how old grinding dosage to be able to produce conglutinate; Increase grinding deepness Ap to be able to bring about grinding force and grinding temperature to increase, conglutinate can increase accordingly. When using CBN abrasive grinding, have slight conglutinate appearance only, because had been compared of CBN emery wheel from acute sex, the grinding force of two kinds of emery wheel can maintain reason to stabilize level for a long time, explained 1 material has Л of Ж of В of CBN arenaceous wheel pair good grinding performance. Of emery wheel wear away with Л of Ж of В of grinding of a few kinds of abrasive the grinding of 1 expresses 3 to show for instance. The grinding that uses alloy of Bai Gangyu or high temperature of grinding of single crystal corundum is lower than be being compared normally, and CBN100# emery wheel has taller grinding to compare below same condition, explain its grinding performance is good; Grinding of CBN180# emery wheel is lower, explain its are good make exterior conglutinate little from acute sex, comfortable at be opposite В Ж Л the finish machining of 1. Express 3 grinding to be compared than grinding of abrasive WA80# CBN100# CBN180# (G) 1.

174 8.

92 1.

11 note: Grinding condition Vs=25.

8m/s, fr=0.

01mm, VW=0.

67m/min. The unit area of surface roughness of surface of grinding of quality of grinding surface treatment and emery wheel wears a number, grind bead to distributing reach cutting trace to concern. In the surface roughness test of this second experiment, be opposite respectively with 3 kinds of abrasive below same condition Л of Ж of В of high temperature alloy 1 undertake grinding with K24, the contrast of its grinding circumstance sees a table 4. To high temperature alloy in having grinding of feed plane abrasion, the grinding quality of CBN emery wheel does not have clear improvement, in the treatment that using CBN180# especially, exterior quality drops somewhat, the specification is in effect of the grinding in feed is machined is poorer, essence of life is used to grind in the working procedure of final precision work of proposal aborning or grind without feed light, in order to improve its surface quality. Л of Ж of the В that express 4 the 1 exterior quality with K24 is comparative (1 1 of Л of Ж of В of WA80# CBN100# CBN180# of abrasive of alloy of Ra/µm) high temperature.

06 1.

0 1.

93K24 1.

01 0.

886 1.

43 inside result of test of round grinding craft and analysis are in В Ж Л 1 inside when round grinding, offer experimental basis and experience to machine parameter to apply CBN emery wheel, special the test specimen that is F to bore diameter with emery wheel of two kinds of CBN had craft test, experimental result sees a table 5. Can see from inside the watch, grind emery wheel to machine В Ж Л with the circle inside CBN quality of surface of alloy of 1 high temperature is good, surface roughness has clear improvement (<0.

7) , suggest adoption grinding rate is 24000 ~ 30000r/min. The choice of fluid of the grinding in grinding treatment is expressed 5 inside the Ra (µm) A 3 of date of exterior quality experiment that the circle grinds an experiment.

72 B 1.

35 C 0.

70 D 0.

168 note: A -- the test specimen without treatment, b -- the test specimen that uses CBN120# rough machining, c -- the test specimen that machines with CBN180# on experimental B foundation, d -- the test specimen that undertakes abrade polish on experimental C foundation, grinding condition is: Add grinding juice, treatment speed is 24000r/min. Because the heat conduction performance of high temperature alloy is poorer, workpiece caloric per cent is passed into when grinding inferior, a large number of quantity of heat of the generation in grinding are centered in paper-thin grinding to express facing, grinding temperature is very consequently high, make easily exterior burn, produce burn crackle, when exterior metal is contractive, those who suffer in-house metal is diversionary, surface of the workpiece after making grind is shown pull stress harmfully, grinding loss of accuracy, because the attention answers to undertake below the condition with cutting sufficient fluid when this grinding, so that take away more heat in metal cutting to reach,rinse test specimen and emery wheel surface, acquire better grinding quality thereby. Use refrigeration of spray of fluid of oil radical grinding commonly, in order to reduce emery wheel block. The logical choice of grinding dosage in Л of Ж of В of high temperature alloy the grinding of 1 is machined in, the workpiece rate that uses lesser grinding surplus, moderate commonly and medium slant the emery wheel speed that go up. When the surplus that grinding place leaves should compare grinding carbon steel a few smaller, in order to reduce grinding workload, stay commonly when kibble 0.

15 ~ 0.

3mm, when essence of life is ground, stay 0.

03 ~ 0.

05mm. The experiment makes clear, it is better that the linear velocity of emery wheel machines the effect when 25 ~ 30m/s is controlled, also can use high speed grinding (40 ~ 60m/s) , such metallic excision are led and grinding comparing will rise greatly, but must have corresponding equipment and technical measure. Workpiece rate is older to grinding burn influence, grinding should raise workpiece rate appropriately when high temperature alloy, but unfavorable and exorbitant, can cause self-excitation concussion otherwise. 4 epilogue carry the experimental research that to Л of Ж of В of alloy of nickel radical high temperature the grinding character of 1 has, obtained state of surface of force of the grinding below different abrasive, grinding and grinding the circumstance that mainer than waiting character changes along with grinding process, the experience that force of the grinding when reaching essence of life is ground changes along with grinding parameter is formulary, provided reliable basis actually for production, favorable result got in applying actually. CNC Milling CNC Machining