High-speed steel machine uses exterior metallurgy the development of saw blade

6 ～ 2.

2mm(grows thick) of × wide × , every saw blade is average weight 0.

25kg. Is high-speed steel machine using the invalidation form in the process to be: with saw blade? Qiu after? saw blade is handled with temper via quenching, integral hardness amounts to 62 ～ 63HRC, have very big brittleness at the same time, be curved in use process, turn round, incidental brittleness ruptures when the action such as concussion and early failure. Does ② wear away: ?  of mildew of A Chinese-style unlined garment of banter of Liang of  magnesian San denounces school  to carry Yu of Xian knock ニ on the back to see mace all? .

When 1mm, because curium,cut speed to drop and cannot continue to use. The price of high-speed steel plank is 5 ～ about 60 thousand yuan / ton, and saw blade wears away to hold weight of integral saw blade only partly thousands of 1/0. This shows, machine the great waste that creates high-speed steel material with the invalidation of saw blade. The workmanship that high-speed steel machine uses saw blade is quite complex. What form in process of high-speed steel smelt is bulky and distributing not all in all brilliant carbide cannot give through heat treatment eliminate, can use only forging the method gives improvement. The process is made in forge in, as a result of high-speed steel hardness serious, plasticity differs sclerosis of tall, treatment, coefficient of thermal conductivity is small, to prevent to produce crackle, must slow heat 7 ～ are pressed after higher temperature 11 times be out of shape degree undertake for many times forginging hot-rolling. The oxidation layer that arises because of high temperature must be cleaned with acid before forginging every time, lest its make friends enters rolled steel interior. Although pass so complex process, curium the carbide of base distributings to still be paid no attention to sometimes want, expression is mixed for granuality distributing inhomogenous. Afore-mentioned reasons cause high-speed steel machine to use saw blade cost tall, life is low, performance characteristics is not ideal. To solve this one problem, we use exterior metallurgy method, the new-style aircraft that developed ministry of a kind of tine to have high speed hacksaw to cut function, back to have taller flexibility and obdurability uses saw blade. Technique of preparation of 2 saw blade (the machine that 1) technology program uses technology of metal of ooze of ion of double deck glow to be made in low carbon alloy steel uses W of infiltration of surface of ministry of saw blade tine, Mo, Cr, V to wait for alloying element, make age ministry edge tooth profile forms layer of a tall alloy, undertake aeriform cementite next, make alloy layer composition is close to high-speed steel, quench via high temperature again and high temperature temper, make the hardness of exterior alloy layer achieves 62 ～ 63HRC, back hardness achieves 50 ～ 55HRC. (Material of 2) saw blade chooses alloy steel of 20Cr1V1 low carbon to regard saw blade as base material (base material composition: 0.

2 ～ 0.

25% C, 1.

0 ～ 1.

5% Cr, 1.

0 ～ 1.

5%V) , the rolling after classics smelt becomes saw blade semifinished product, make low-alloy steel saw blade via issueing makings, gear-shaping, shunt again. Choosing mild steel is to accelerate the infiltration rate of ooze metal technology, because W, Mo, Cr, V all is carbide to form an element, form carbide easily in ooze metal process with carbolic action, block up alloying element continues infiltration, restrict ooze layer ply thereby. Choose 1 ～ 1.

Element of the Cr of 5% , V is to make matrix has higher temper by dipping in water to show gender and strength, and in ooze metal technology matrix grain is prevented for long to be brought up when high temperature heats. Place of ooze metal technology uses scale of source pole material to be: W: MO:CR:V=9:4: 1: 2. Of ooze metal surface book target composition to be about: 9%W, 3%Mo, 1%Cr, 1%V. Among them, w, Mo is the main element that forms enough carbide, by high-speed steel medium alloying element deserves to compare add: Machine the effective ply that uses saw blade is about 2.

2mm, add the Cr of 1% to be able to satisfy temper by dipping in water to show a demand: Joining the V of 1% is to raise wearability, because the carbide hardness in the V in high-speed steel is highest and wearability is best. It is in source pole the another account that adds Cr, V is to be in ooze metal process, of ionic bombard splash shoot action to meet matrix surface element of one part Cr, V is splashed shoot, it is certain to be joined in source pole it is certain that proportional Cr, V can make up for ooze layer surface of element of the Cr inside area, V decrease, in order to assure the composition of ooze layer and saw blade performance characteristics. (: of technique of parameter of technology of 3) ooze metal? Qian of  of alliance of take along sth to sb complains Yu Guang to a concubine of an emperor by rice huller of carbohydrate of San of imperial mandate of Liang of border of Shou of  fish hawk 500V of ～ of?400 of Miao of  of ぜ of  acyl sweat: Source pole voltage: 900 ～ 1000V: Working temperature: 11150 ℃ of 120 ～ : Ultimate pressure: 1Pa: Working vacuum is spent: 30 ～ 50Pa: Heat preservation time: 8～ 10h: Cooling means: 650Pa fan is cooling. (: of technique of parameter of 4) cementite craft?  directly  ? wears close condole to hang) side by side: Cementite temperature: 925 ℃ : Heat preservation time: 6H: Situation of the carbon inside furnace: 1.

0% : Connect gas: CH4+N2: Cooling means: ? A person of extraordinary powers enters oily refrigeration after 1h of heat preservation of ℃ of?60 washing with watercolors to room temperature. (Does 5) quench reach: of temper parameter technique? Lie Qian of ÷  Gua ferociouses dash forward 3min of × of ℃ of 10min + 1200 of × of ℃ of?860 of dew of snipe of Qian of Tao Se defend, into 60 ℃ oil refrigeration comes room temperature, temper of clamping apparatus of traditional Chinese clothes of salt of 550 ℃ saltpetre 3, use fan wind every time cold to room temperature. Sample of 3 saw blade detects result (after organization of metallographic of 1) ooze layer and technology of metal of composition course ooze are handled, if the graph is shown 1 times,the metallographic of layer of W-MO-Cr-V alloy ooze is organized, the perpendicular distributinging curve of composition of ooze layer alloy is shown 2 times like the graph. Graph the metallographic of layer of ooze of the alloy after 1 ooze metal is organized (125 × ) graph after the distributinging curve of composition of alloy of layer of the ooze after 2 ooze metal passes craft of ooze metal, cementite to handle, if the graph is shown 3 times,the metallographic of ooze layer is organized, the electric lens photograph of microstructure is like ooze layer the graph is shown 4 times. Graph the metallographic of layer of the ooze after 3 ooze metal, cementite is organized (125 × ) pursue the microstructure of layer of the ooze after 4 ooze metal, cementite (electric lens 2000 × ) (2) quenchs, temper metallographic organization and hardness course quench, the alloy after temper heat treatment, the perpendicular distributinging curve of ooze layer hardness is shown 6 times like the graph. Graph 5 quench, the ooze layer metallographic after temper is organized (125 × ) graph fretsaw of hardness profile music cuts 6 ooze layer function detects time of cutting of number of result watch sample (Min) wear rate (wear rate of requirement of level of time of cutting of %) standard requirement 141.

81%243 of ≤ of 67 ≤ 80min.

2828339.

315438.

315542.

Test of 3519(3) cutting function presses British standard BS1919-1983 as a result in the concerned provision that concerned machine uses saw blade undertook to saw blade sample function checks curiuming cutting, detect via quality of national cutting tool the center examines. Detect the result sees right table. 4 analysises and discuss (W of analysis of organization of 1) ooze metal, Mo, Cr and V all belong to the element inside contractible γ area, and Cr, V but with α - dissolve of Fe infinite each other. Phase begins in ooze metal, matrix organization is in austenite condition, when alloying element infiltration, form W, Mo, Cr, V to be in above all γ - the solid solution in Fe: When content of matrix surface alloying element reachs certain consistency, form W, Mo, Cr, V to be in in matrix surface namely α - the nucleus in Fe [4] : The extension as ooze metal time and exterior alloy pH indicator are farther heighten, nucleus is brought up ceaselessly, show columnar brilliant is ceaseless and inward outspread. Right now, the W that forms certain ply in the surface, Mo, Cr, V is in α - the solid solution in Fe, its forward position is the W with thinner ply, Mo, Cr, V to be in γ - the solid solution in Fe, its interior is austenite matrix. Right now, high temperature organization distributings for (reach by the watch in) : W, Mo, Cr, V is in α - the W of solid solution → in Fe, Mo, Cr, V is in γ - the matrix of austenite of solid solution → in Fe. In α - Fe and γ - apparent interface arose because of crystal structure difference between Fe, and be lengthened as time and exterior chroma heighten is inward ministry parallel elapse. When heat preservation end undertakes cooling, when temperature under change dot, w, Mo, Cr, V is in γ - the solid solution in Fe and austenite matrix happen to change, the α that change is structure of body heart cubic metre - Fe, and the α when high temperature - Fe and γ - the interface that forms between Fe criterion because change,the fault matchs atomic of time interface crystal lattice to arrange and be come down by reservation, become the interface of layer of the ooze in metallographic organization and matrix. Accordingly, organization of formation room temperature metallographic is: W, Mo, Cr, V is in α - the solid solution in Fe + α - Fe matrix organization. (When 2) cementite organization analyses cementite, because temperature is inferior () of temperature of recrystallization of summary prep above, because this grain is fine small, crystal boundary and form nucleus position are more, the solubility of alloying element is small, have the chemical driving force that takes off dissolve separate out from inside matrix, element of together with W, Mo, Cr, V all easy form carbide, and right now carbon diffuses with clearance means infiltration, its diffusion coefficient is bigger than alloying element 1 ～ 2 amounts class. Alloying element and carbolic atom form many carbide nucleus inside shorter time, because form nucleus leads tall, nucleus small and metallic atom diffuses speed is brought up slow, not easily, the carbide that forms accordingly is petty and even. (3) quenchs temper organizes an analysis to quench temper organizes matrix of martensite of the brilliant that it is concealed + graininess the petty carbide that distributing. Diffractive to the X ray that photograph structure undertakes analysis makes clear, carbide type is M6C and M7C3. (4) cutting function analyses cutting experiment to make clear, high-speed steel machine uses exterior metallurgy the ooze layer organization of saw blade is normal, carbide grain is petty, have very tall hardness and wearability. Organization of saw blade matrix is the body of family name of shellfish of high temperature temper with tiny grain or troostite, hardness is tall, obdurability and flexibility are good, the intensity that prop up and fight concussion ability (become bunch of rolled steel in successive cutting especially when) saw blade of excel whole high-speed steel. (Metallurgy of surface of analysis of 5) application foreground high-speed steel machine uses low alloy material to make with saw blade, cost is low, cost of raw materials only 2.

0 yuan / , add follow-up working procedure to handle charge to also do not exceed 5.

0 yuan / : And high-speed steel machine uses whole saw blade only cost of raw materials needs ten yuan / , add sequel to handle cost cost to be 15 yuan about / , and existence alloy material is wasteful serious, workmanship is complex, easy fragile break wait for a problem. At present domestic machine is 400 ～ about with demand of saw blade market 6 million / year, if popularize saw blade of high-speed steel of applied surface metallurgy, can reduce finished cost substantially, improve treatment quality and efficiency, managing material resource. This technique still can popularize application to ask to win the work of surface of tall hard wear-resisting at other. 5 conclusion use technology of plasma ooze metal to be able to form the tall alloy layer that metallurgy combines in surface of low carbon alloy steel, can press anticipate the requirement designs constituent of control alloy layer and ooze layer deepness through craft. Can make through cementite method tall alloy layer is achieved or the part that approachs high-speed steel and function, obtain carbide petty (granuality relatively the carbide in metallurgy high-speed steel is small 1 ～ 2 amounts class) , distributing even, do not have in all the exterior cementite of bulky carbide organizes brilliant. The exterior metallurgy high-speed steel that obtains through craft of ooze metal, cementite can undertake warming up quenching reaching temper directly, the exterior metallurgy that preparation gives high-speed steel machine comparatives with function of saw blade cutting and saw blade of smelt high-speed steel, hardness of saw blade back under tine ministry hardness, have taller obdurability, not easy fragile break, and saw blade cost is reduced substantially. CNC Milling