Craft of milling of helix of aperture of titanium alloy big diameter optimizes research

  • Time:
  • Click:227
  • source:AMANCIO CNC Machining
Core clew: The article is based on technology of helix hole milling, use orthogonal experiment and method of analysis of extreme difference value, undertook on titanium alloy 19.

The helix milling of 05mm diameter aperture experiments. The effect that analysed countershaft of different cutting parameter to wait to aperture of alloy of cutting force, titanium, surface roughness, optimize an optimal craft parameter for index with this. Studied on this foundation quality of force of the cutting below optimal parameter, treatment and cutting tool wear away to change along with what machine Kong Shu, in sending aperture of big now diameter to machine, technique of helix hole milling can improve treatment effectively quality, improve treatment efficiency. As the development of aerospace industry, taller and taller to making the demand of aperture precision and exterior quality, the application of titanium alloy is wider and wider also, at present titanium alloy is the metallic stuff with aerospace essential industry not only, there still is wide application in the industry such as industry of medical apparatus and instruments and tool, metallurgy, shipbuilding. But titanium alloy intensity is high, hardness is big, thermal conductance is low, heat in metal cutting comes loose not easily piece, cause cutting tool to wear away serious, affect cutting tool service life badly, treatment surface quality is poorer and efficiency is low. The cutting tool when helix hole milling moves to be formed by face of tripartite of feed of the rotation of cutting tool, revolution, axial, cutting tool center shows corkscrewed yarn contrail, it is a course that gets with mill belt, be helpful for cutting bits eduction and medicinal powder hot (1) seeing a picture. This technology can reduce axial force considerably, improvement makes aperture quality, improve the efficiency that make hole, still can pass adjust offset comes true conveniently " one knife much diameter " , gain the favour of aviation manufacturing industry. The helix hole milling that Liu Gang studied to be based on the principle that divide bits is special cutting tool, right the different cutting action of ministry of the effect dividing bits of special cutting tool, end and blade of side edge cutting and cutting tool service life undertook an analysis. Wang Haiyan, Wei Min cutting tool to parameter of different point of view undertakes finite yuan 2 dimension are emulated, define scope of appropriate cutting tool angle, designed helix hole milling special cutting tool, had kinetic research to helix hole milling. E.

A.

Rahim studied the cutting tool blade influence to milling cutter function. The part after Jamal Ahnmad points out cutting tool of helix hole milling is larger to cutting power influence. Of the research such as Chatelian alveolar model helix milling cutter has good cutting performance. Chan Yicai studied CFRP/Ti6Al4V craft, put forward big pitch hole milling to fold the craft advantage of a component to treatment. Li Dengmo optimizes titanium alloy to machine parameter through devising a method equably, improved cutting efficiency and exterior quality. Chen Ertao is based on the cutting parameter such as deepness of cutting speed, cutting and every tine feed, built treatment parameter to optimize a model. King Feng Chao studied through the experiment different cutting parameter is right the influence that exports deviation of burr height, aperture and surface roughness. Graph plane of graph of principle of 1 helix hole milling is assembled in the aperture amount under diametical 1/2 ″ is maximum, because the research of technology of this helix hole milling is much,center hereat. But in the key bear power position still has a certain quantity of big diameter opening, treatment is very difficult. Current, treatment of big diameter aperture is used normally auger, the many working procedure such as enlarge, bore with a reamer, technology is sophisticated, need tens of cutting tool, finished cost is high, treatment efficiency is extremely low, it is a plane all the time one of difficulty in assembling. It is with milling cutter of 12mm diameter helix exemple, use the method such as orthogonal experiment and extreme value analysis to undertake titanium alloy 19.

05mm(3/4 ″ ) the research of technology of helix hole milling of big diameter, analysed the different parameter effect to machining quality, optimized optimal treatment parameter. Research is helpful for driving helix hole milling to process medium application in big diameter aperture, assemble to raising a plane at the same time it is efficiency, important to reduce finished cost to also be had meaning. 1 test equipment and the physical function that experiment design expresses 1 titanium alloy and mechanical function dependency can 1.

1 test equipment and material experiment place are with cutting tool without cutting tool of hole milling of helix of coating hard alloy, diametical 12mm, machine bore diameter 19.

05mm, helix angle 35 ° , before horn 8 ° , hind horn 15 ° , cutting tool blade is counted 4, use dry cutting means. Trial work material is titanium alloy board, ply 5mm, size is 120 × 250mm, the physical function of titanium alloy and mechanical sex visibility are expressed 1. Machining center is 5 number of axle of DMC75Vlinear to charge a machine tool, use 3 to Kistler 9257A the appearance that measure power detects cutting force, the amplifier of charge of signal classics Kistler 5007A that detects is transmitted, data collects card to undertake collection, by Dynoware software of the appearance that measure power is undertaken real time shows; Use Wenzel LH65 3 coordinate measuring instrument undertakes bore diameter detects, every aperture undertakes sampling got bore diameter data at 4 o'clock; Surface roughness is measured use detector of 3 abundant surface roughness, use exceed microscope of depth of field to observe cutting tool wear out condition. Express parameter of 2 orthogonality experiment to express   1.

2Design of experiment of Ti-6Al-4V craft cutting uses cutting tool of 12mm big diameter to machine 3/4 ″ (19.

05mm) aperture. The particular trial parameter that 3 levels orthogonality experiments sees 3 factors watch 2. Among them, pitch states cutting tool of every revolution a week is down the distance of feed, tangential every tine feed states every cutting blade is tangential the ply of cutting. Every groups of experiments machine two aperture, what measure parameter to take average. 2 tests result and analytic   2.

Parameter of 1 different treatment pursues to the influence rule of cutting force 2 it is the 3 follows time change to cutting force curves that measure below condition of parameter of the 5th group of cutting, definition Z axis is direction of axial cutting force. Can see from inside the graph, the condition of metabolic wave motion of X Xiang Li and Y Xiang Li is fundamental the trend is consistent, axial force changes inside certain limits, choose stable cutting phase to regard effective cutting as force, the cutting power that measures below each parameter sees a table 3. N=1800r/min, pitch α =0.

25mm, tangential F=0 of every tine feed.

025mm/z   pursues the 2 cutting force signal that measure along with time change place pursue 3 it is the extreme difference that is a target with axial cutting force analytic result. Can see from inside the graph, pitch is the main factor that affects force of cutting of cutting tool axial, it is next tangential every tine feed, the smallest to influence of axial cutting power is main shaft rotate speed. Graph value of extreme difference of 3 cutting power expresses force of 3 axial cutting to turn test result on average 2.

The influence of parameter of 2 different treatment to bore diameter precision one of main index that bore diameter precision is the quality that make hole, enlist in army to what the plane assembles quality and component part life has main effect, the aperture that used experiment of 3 coordinate measuring instrument to study different parameter falls machines precision (4) seeing a table. From the measurement of bore diameter the result can reach, titanium alloy aperture machines tolerancepublic errand grade to all be between IT5-IT7, the 5th group of bore diameter grade that machine parameter are IT5, bore diameter error is the smallest. Use extreme difference to analyse a law to analyse treatment parameter the influence rule to bore diameter, the extreme difference value that reach sees a picture 4. Main shaft rotate speed and tangential the main factor that every age feed is influence aperture, pitch is lesser to the influence of bore diameter. Graph 4 aperture extreme difference is worth   2.

Parameter of 3 different treatment is the main factor that evaluates Ti-6Al-4V surface to machine quality to the influence surface roughness of surface roughness, the plane is assembled in have firm demand to its, the hole wall surface roughness that gets below different parameter sees a table 5. Express surface roughness of 5 orthogonality experiment to measure in process of helix hole milling, bore diameter surface roughness is worth in 0.

18-0.

When 42 μ M, hole wall is bright and clean degree wonderful. Use extreme difference law to analyse the treatment parameter effect to surface roughness, gotten extreme difference value sees a picture 5. Can see, the biggest to influence of hole wall surface roughness factor is tangential every tine feed, it is main shaft rotate speed next, the impact is the least is pitch. The place on put together is narrated, in order to reduce axial cutting force, reduce bore diameter error, raise hole wall quality to be main goal to undertake parameter optimize. The 5th group of axial cutting force that machine parameter and bore diameter error are the smallest, the hole wall surface roughness of the 7th group of parameter is the smallest. Consider surface roughness value is far be less than a plane to make a standard, and the 5th group of surface roughness values and the 7th group differs only 0.

055 μ M, reason chooses the 5th group of parameter to be hole milling of big diameter helix craft of best treatment parameter. Aperture of 3 big diameters machines quality to follow the metabolic rule that machines Kong Shu to be based on above to analyse, studied quality of cutting force, treatment and cutting tool wear away to follow the metabolic pattern that machines Kong Shu below optimal treatment parameter. 3.

The change of force of 1 axial cutting is best force of cutting of the axial below cutting parameter follows the change that machines Kong Shu to see a picture 6. Because cutting tool adjusts level cutting process to be not stabilized, bring about the 2nd aperture and the 3rd cutting force of aperture to greaten suddenly; Subsequently, cutting tool is entered wear away normally level, cutting force rises gradually, but scope is very little, machine force of cutting of the axial after 30 aperture to be controlled in 100N as before. 3.

The change of the surface roughness below 2 best parameter is best the variation that the surface roughness below parameter counts along with treatment aperture sees a picture 7. Can see, the surface roughness of before 20 aperture is in basically 0.

2-0.

Fluctuate between 3 μ M, but the surface roughness of the 20th aperture is apparently elevatory, be in again subsequently 0.

4 μ M controls wave motion. Overall for, the hole wall surface roughness of hole milling of big diameter helix increases along with what machine Kong Shu and lift, but span is lesser (0.

2-0.

Between 4 μ M) , accord with the requirement of aviation manufacturing industry to hole wall surface roughness completely. 3.

The change of the aperture below 3 best parameter is best the variation that the aperture below cutting parameter counts along with treatment aperture sees a picture 8. Can see from inside the graph, the diameter that machines early days is stabler, in 19.

07mm controls wave motion; The aperture after the 13rd aperture appears bigger wave motion, this basically is by titanium alloy felt and cutting tool wear away be caused by. Can pass considering helix hole milling adjust the compensation of error of offset implementation aperture, the bore diameter precision that with its consequently quantity of the biggest change evaluates this craft is more effective. With standard aperture 19.

05mm photograph is compared, the biggest error that processes bore diameter is 0.

03mm, error value is little, treatment result is favorable. 3.

4 cutting tool wear away form appearance pursues 9 wear away to machine the cutting tool after 30 aperture form appearance, of cutting tool side edge wear away dinky, almost observation does not arrive, and blade body is basic also and whole, did not produce collapse blade (9a) seeing a picture; Graph 9b wears away for point of a knife form appearance, face of the knife after point of a knife appears apparent titanium alloy felt, the specification produced felt to wear away here; Graph 9c and graph 9d are blade of cutting tool bottom hind knife face wears away form appearance, can see produced small collapse blade, wear away from what blade seeing an end comes on wear extent more serious than side edge. Accordingly, wear away the most serious blade that it is a bottom, and outside place of side point of a knife is the most serious, because blade of the bottom in process of helix hole milling is successive cutting,this is, and feed of every tine axial is dinky (0.

) of tine of 28 μ M/ , hind the attrition between knife face and workpiece is more serious, reason cutting temperature is high, felt wears away, oxidation wears away aggravate; Stand by point of a knife more, cutting rate is higher, bring about wear away serious. Graph aperture of 8 titanium alloy is worth a graph cutting tool of 9 titanium alloy wears away the graph no matter side edge or bottom blade, milling after 30 aperture, wear extent is far did not achieve 0.

Of 3mm grind blunt standard, the specification machines parameter to fall here, cutting tool can machine Kong Shuyuan to be more than 30. The treatment of aperture of big diameter of alloy of titanium of 4 brief summary is the difficulty that aircraft manufacturing industry machines all the time, conventional technology needs to use a variety of craft such as the bore with a reamer that get enlarge, much method working procedure and tens of cutting tool, take time is arduous. Be based on technology of small loss, efficient helix hole milling, through orthogonality trial law undertook the treatment craft of aperture of 3/4 ″ big diameter optimizes research, get the following verdict: Be based on orthogonal experiment and method of extreme value analysis, analysed different treatment parameter big to titanium alloy diameter (3/4 ″ ) precision of force of the cutting when helix hole milling, aperture and hole wall surface roughness the influence that wait, discover the biggest to axial power influence is pitch, and main shaft rotate speed and tangential the main factor that feed is influence aperture precision, tangential the main factor that feed is surface roughness of influence hole wall. Consider cutting force and treatment quality integratedly, optimize reach the optimal cutting parameter of hole milling of big diameter helix is: N=1800r/min of main shaft rotate speed, pitch Ap=0.

25mm, radial feed F=0.

025mm/ tine, right now treatment efficiency is 147.

7s/ aperture. Use the treatment parameter after optimizing to undertake helix hole milling experiments, as treatment Kong Shu increases, cutting force shows small to lift, after machining 30 aperture, aviation of treatment quality far excel makes a standard, and cutting tool wears away slight, the treatment of hole milling of helix of big diameter of alloy of can contented titanium asks. CNC Milling CNC Machining