Durability of cutting tool of milling 30CrMnSiNi2A steel affects research

30CrMnSiNi2A of steel of extra high strength is the structural stuff with a kind of good integral performance, high intensity, good via can be being obtained after heat treatment plasticity and the fatigue resistance with gender, good pliable but strong can be mixed fracture toughness, low fatigue crackle is patulous rate [1-2] , cooling in oil, temper by dipping in water appears a gender sectional diameter can amount to 50mm above, have important place in aviation industry consequently, basically use at making the component part getting power such as plane landing gear. As the grow in quantity of machine tool of domestic numerical control, the performance that increasingly outstanding issue is a machine tool is higher and higher and treatment efficiency is apparent on the low side, create the enormous waste of machine tool resource thereby, the cutting dosage with reasonable cutting tool, logical choice and proper cooling way are one of important step that solve this one problem [3] . The article carries the research of force of pair of the cutting when steel of 30CrMnSiNi2A of milling of cutting tool of coating hard alloy and cutting tool durability, and the analysis that cooling means affects to cutting tool durability, for cutting this material chooses reasonable cutting dosage and cooling means to provide guidance, be cutting parameter optimize offer tie condition. Experiment condition and plan 1 experiment condition (1) experiment instrument. Swiss Kistler9257B Che Xi measures power instrument; The portable cutting tool that Beijing aerospace university develops wears away detector. (2) test data. 30CrMnSiNi2A steel, the dimension of test specimen is 93mm of × of 160mm × 130mm. (3) experiment machine tool and cutting tool. Milling cutter of face of FMR01-040-XP32-RC12-03 of diamond of individual plant continent is used on vertical machining center, cutting tool diameter is 40mm; Bit material is coating hard alloy character, the brand is GC2040. 2 tests program uses orthogonal trial law to design cutting force to experiment, test result uses processing of law of multivariate and linear regression. Use 4 ingredients the orthogonality of 4 levels expresses L16 (44) , if test program expresses 1 to show. In the experiment, use sheet to age suitable milling means undertakes. According to international general standard, ＝ of VB of wear extent of face of the knife after choosing 0.

3mm serves as cutting tool grind blunt standard, the experiment cent is the following two groups. (1) have cutting fluid cutting: Wear away to cutting tool considering radial cutting width the influence is minor, introduce 3 elements (cutting speed, feed and axial cutting deepness) test program has a test, discuss the concern of milling dosage and cutting tool durability, if experiment cutting parameter expresses 2 to show. (2) without cutting fluid doing cuts: Durability of a group of cutting tool is chosen in result of advanced interview test longer cutting parameter has a test, contrast studies condition of two kinds of experiments lays the wear out condition of cutting tool. Result and the relationship that analyse 1 cutting force and cutting parameter undertake recursive an analysis to expressing 1 medium data, get Fx (radial cutting force) , Fy (tangential cutting force) , Fz (axial cutting force) the model is as follows: Use F to assume inspection undertakes the significance of the model examines recursive, the ＝ of F of statistical value of a quantity that gets recursive a model via computation 46.

8564, check F distributinging watch to know, when A=0.

05 when, f=4.

84<46.

8564, from this knowable, returning to gotten milling force model is height is remarkable, can forecast with what cut force at mill. The influence of dosage of the milling below action of 2 cutting fluid to cutting tool durability Nextpage basis experiments plan, in cutting fluid action falls, by the watch 2 ranks order has a test, each cutting tool is achieved grind place of blunt standard accumulative total to if the watch is shown 3 times,use time. To the watch 2 with the watch 3 medium data undertake multivariate regression, get cutting tool durability returns to a model: In type, v is cutting linear velocity; Fz is every tine feed; Ap is axial cutting deepness; T is cutting tool durability. Use F to assume inspection undertakes the significance of the model examines recursive, the count that gets recursive a model via computation measures value F=18, check F to distributing the watch is knowable, when A=0.

05 when, f=6.

61<18, accordingly, returning to model of gotten cutting tool durability is height is remarkable, can provide durability to forecast with Yu Dao. Generally speaking, cutting rate is the oldest to influence of cutting tool durability, feed take second place, cutting deepness impact is the least [4] , this and 3 person concern to the influence of cutting temperature. And from type (2) can see, the durability of this cutting tool just as contrary as general situation, cutting deepness is the biggest to influence of cutting tool tatty, feed take second place, cutting speed impact is the least. Graph 1 it is in cutting tool enlarge 100 times circumstance falls, face of the knife after the cutting tool when experiment serial number is 12min for time of Ⅲ and Ⅴ , cutting respectively wears away exterior graph, from the graph 1 knowable, of this cutting tool wear away the form is given priority to with crackle, contain form of damaged of attrib border tatty. As a result of,this is: Cutting deepness increases, cutting force increases, force is bumped to increase when cutting tool cuts work, fall however in cutting liquid cooling at the same time, cutting tool suffers hand in heated stress and bump force joint action, damaged of cutting tool occurrence crackle, accompany certain border to wear away. Cutting of refrigeration of fluid of 3 comparative cutting and dry cutting affect cutting tool to be in what cutting fluid refrigeration falls to wear away to cutting tool durability for crackle damaged form, dispute wears away normally, because cutting liquid cooling is caused however,the likelihood is. To confirm this one likelihood, the parameter of a group of cutting with better durability of the cutting tool in choosing afore-mentioned experiments undertakes cutting experiments working again, express namely 1 in the cutting parameter that experiment serial number is Ⅱ correspondence. Photograph of contrast of tatty of the cutting tool when getting 2 show cutting fluid cutting and dry cutting pursueing, and draw gives a picture when 3 show cutting fluid cutting and dry cutting, the wear curve of cutting tool leaves in different cutting time. Test result makes clear, v=196m/min, Fz=0 is in cutting parameter.

Below 25mm, Ap=2mm, Ae=24mm, when cutting fluid cools, cutting tool durability is 48min, and the cutting tool durability when dry cutting is 94min. From the graph 2 show the wear curve that photograph of contrast of cutting tool tatty and graph show cutting tool 3 times to be able to see, durability of the cutting tool when cutting of refrigeration of fluid of cutting of excel of durability of the cutting tool when dry cutting. Because fall however in cutting liquid cooling,this is, workpiece and temperature of cutting of cutting tool interface are high, workpiece and temperature of interface of cutting tool blame are low, put in very tall temperature gradient in cutting tool surface, cutting part surface bilges because of be being heated up repeatedly cold shrink, generation hands in heated stress tremendously, make blade point point produces fatigue craze thereby, occurrence crackle damaged. Do the cutting temperature when cutting tall, temperature gradient is small and distributing to be stabilized equably, cutting tool basically wears away with attrib border attrition give priority to, appear not easily collapse blade and crackle, cutting tool durability is consequently longer [4-5] . Conclusion passes cutting experiment and recursive analysis, the 3 Xiangli models when obtaining cutting tool of GC2040 coating hard alloy to issue milling 30CrMnSiNi2A steel in cutting fluid action reach model of cutting tool durability. (1) the milling force model that regression gets is height is remarkable, can forecast with what cut force at mill; Cutting deepness is the biggest to influence of cutting tool tatty, it is feed next, cutting speed impact is the least. (2) fall in cooling fluid action, cutting tool is incidental be not form of normal tatty breach damaged, make the service life of cutting tool is reduced. (3) when cutting parameter V=196m/min, Fz=0.

When 25mm, Ap=2mm, dry milling 30CrMnSiNi2A can improve the service life of cutting tool significantly. Optimize about what Gan Xi cuts parameter, remain to study further. CNC Milling