High-speed steel of newest the 3rd acting pulverous metallurgy

W Taylor) and bosom of division of Cheng of smelt metal metalworking are special (M.

White) is in the course is extensive and after systematic cutting experiments, establish the optimal composition W18Cr4V(C 0 that cutting uses high-speed steel.

75% , w 18% , cr 4.

0% , v 1.

0%) , speed of cutting medium carbon steel is 30m/min at that time, ten times rise before comparing. This one achievement brought the epoch-making revolution of machining, also because this makes,cutting tool data appears an unconventional development speed after entering 19 centuries, created unprecedented brilliant. Come 100 years, although appear ceaselessly all sorts of new cutting tool material, but high-speed steel still was not washed out by historical place, all the time continue to use develops up to now, ever held number one position for a long time even. Today, we examine the development of high-speed steel afresh, bring the further progress that is cutting tool material a few beneficial inspiration probably. Here, also along with all the others Zhao Bingzhen, Wu Yuanchang, Zhao Buqing, Wu Lizhi 4 experts seductively dressed or made up in the river the speech content that 2006 high-speed steel apply technical communication to be able to go up arranges existing writings, in order to provide dinner for reader. Pulverous metallurgy high-speed steel (PM HSS) it is the top grade in high-speed steel, works of domestic most tool has an ambiguous idea only to it, knowing it only is the advanced high-speed steel with a kind of good performance, and do not know to exist at the same time on our country market at present the 1st generation with quality, chemical class status is same and different function, the 2nd generation and the PM HSS of the 3rd generation that just develop at the beginning of 21 centuries. The century on development of pulverous metallurgy high-speed steel and recent situation at the beginning of 70 time, PM HSS by Swedish Stora factory (belong to French Erasteel company now) throw industrialized production above all, this is generation PM HSS, the content of metalloid field trash of its rolled steel comparatives level of refined of bag of steel of the LF after electric arc furnace. Swedish Soederfors factory used ESH technology 1991 (electric broken bits heats law) , make steel more pure, compare with generation PM HSS, content of metalloid field trash can decrease 90% , bending strength can rise 20% , the PM HSS that uses ESH technology production calls the 2nd generation, brand of this company product also is changed for ASP 2000 series, be like: Steel is planted ASP 2030. And its the 1st acting product weighs ASP 30, both chemistry becomes split phase to be the same as. French Erasteel company rises from 2002 to its the manufacturing whole journey of the 2nd acting ESH PM HSS undertook study, after making several improve, since 2004 its product brand weighs Dvalin, of all production reach product of delivery of cargo from storage to all press this new standard, it is the 3rd acting PM HSS of this company. After the 2nd acting PM HSS of this company uses ESH technology, reduced the metalloid field trash of 90% than generation, and the 3rd acting Dvalin PM HSS reduced another metalloid field trash of 90% again than the 2nd generation. If with dimension of M of the 50 μ in every 1cm3 steel the amount of metalloid field trash plan, traditional or the 1st acting PM HSS is 0.

6, of the 2nd generation for 0.

03, and of the 3rd acting Dvalin for 0.

002. Watch normally M42 steel is mixed the 1st, the 2nd, the transverse bending strength of the 3rd acting PM HSS changes (steel plants the 67HRC) after temper of temper by dipping in water normally M42 the 1st acting ASP 30 the 2nd acting ASP 2030 bending strength of the 3rd acting Dvalin ASP2030 (GPa)1.

33.

0 3.

54.

Of 2 metalloid field trash a large number of reducing, make the bending strength of PM HSS chases era to increase, it is with the transverse bending strength that determines from the sampling on φ 100mm rolled steel exemple, fusion ingot casting normally M42 steel, 1 generation goes to pass an imperial examination the 3rd acting PM HSS 2030(S6.

4-5.

0-3.

1-8.

The bending strength change of 5) sees right table. The corresponding cost that the intensity of the 3rd acting PM HSS Dvalin ASP2030 compares the 2nd acting ESH ASP2030 increases again 20% , the cutting tool that this makes be made can bear greater cutting stress and more impulse withstand bear. Tool surface blemish is like hard alloy photograph to compare to the influence of tool function and other tool material, a of ASP steel the most distinct advantage is its high strenth. This makes tool maker can make sharp cutting tool not only, and the user that can allow them uses big feed and rate of workpiece material purify, the tool is used below high load capacity. The high strenth of PM HSS results from its are had distinctly high pure spend the couple with fine microstructure completely, make the level of blemish of its interior material extremely low. Because the level of in-house blemish in PM HSS is inferior,reach size lesser, because as a result of,this makes the manufacturing process of the tool (blame steel " immanent " quality) the tool surface blemish of generation has huge possibility to become bigger drawback, the exterior blemish that because introduce in tool production process,this means can make because of the high quality of integral material expectation gets high strenth always can not come true certainly. Often bear for the tool because of tool surface highest stress part, the blemish of tool surface often also makes tool life restrict an element. The exterior quality of a tool is in the tool the result that in making, different treatment measure forms, wait like preparation of heat treatment, grinding, last face. The function with ultimate tool loses by force decide the exterior quality at the tool. Exterior quality acquires from following combination: Of the surface " geometrical property " : Exterior surface roughness, the exterior blemish of existence is like grinding nick. Compare with material whole photograph, be close to exterior share data " organization, machinery and chemical changes " . If posture change, heat affects area, cementite, decarbonization, oxidation, leftover stress, plasticity,be out of shape etc. Other blemish is like burr. High-powered PM HSS constant because its are tall alloy content and can heat treatment arrives a higher hardness level (66~70HRC) , but general tenacity will be poorer. Tool maker still can have enough tenacity to the cutting tool of tall hardness to make temper by dipping in water hard, should very the exterior surface roughness that notices to improve cutting tool point. The high-speed steel of hardness 65HRC, ra0 is in exterior surface roughness.

When 5 μ M, bending strength is 5GPa; The high-speed steel of 70HRC of another kind of hardness, ra0 is in exterior surface roughness.

When 2 μ M, also can achieve the bending strength of 5GPa. Afore-mentioned can come true on latter-day PM HSS only. Our country of use current situation of our country PM HSS is high-speed steel uses big country, crop of rolled steel of true 2005 high speed is made an appointment with 3.

70 thousand tons, consume a circumstance by international high-speed steel, our country should use 4500 tons of PM HSS, but connect 40 tons to be less than actually. PM HSS of visible our country still handles illuminative level with material. Want to change this kind of condition, the key is wanting change thinking at the leader, want to consider be eager to make progress. Even if cultivate milling cutter of form annulus chamfer,the most typical case is. Abroad uses PM HSS already 30 old, already changed steel one round to plant in recent years, the cutting life with taller in an attempt to, and home still is using M42 steel changeless, at present the cutting life of product of this knife abroad already 2~3 times at homebred, this knife imported nearly 1 2005 100 million. Only tool producer can aim at world brand, be eager to make progress is sought on quality, going up with material think of an innovation, the ability on the our country use in PM HSS cutting tool and production is benign develop, only PM HSS uses face and quantity to expand, ability promotes the development of PM HSS. Our country has following cutting tool to already applied PM HSS: Do angrily annulus hob (140~180m/min) , even if cultivate milling cutter of form annulus chamfer, milling cutter of root of bacterium form leaf, bimetallic takes zigzag hob, milling cutter of arc tine bevel gear, hob of high speed gear (100~120m/min) , insert tine knife, broach of aviation leaf root. Because author contact is finite, have surely not remark person. PM HSS steel of application plants have: ASP2052, S390(S10.

5-2-5-8) , CPM T15, ASP2015(S12-0-5-5) , CPM M4HC, S690(S6-5-4) , ASP2030, S590(S6.

5-5-3.

1-8.

The brand such as 5) , S790(S6-5-3) . The user can be chosen according to the condition offerring money of manufacturer of different PM HSS. The PM HSS that the author does not understand very and steel of tool of PM TS(pulverous metallurgy) domain of another broad application is mould industry. The mould is tall to material quality requirement, all choose high grade raw material. Mould data vendor is weathy, can fall in the condition that does not have enough understanding to PM HSS, be being ordered is several tons, the brand is given priority to with CPM M4 and ASP2023. The first batch when Wu Kelan exports our country 20 tons of PM HSS, most subscriber is businessman of Shenzhen mould material. The author already had encountered the user that must provide rolled steel to be able to satisfy product service life with pulverous metallurgy Leng Zunmo. Existing die uses Cr12MoV steel to be able to acquire life 500 thousand times, and user requirement is repaired every time grind life to be 5 million times, change only with pulverous metallurgy Leng Zunmo provides steel, just go with same material with abroad, mould industry will become PM HSS domain to compare pillar of tool industry stronger. In addition spaceflight uses gear pump, once develop,also must be raw material with PM TS. Our country generates electricity this year installed capacity amounts to 75 million kilowatt, house world the first, each turbine factory job is busy. Car output will break through 4 million, house world the 4th. Crucial turbine cutting tool, sedan cutting tool is divided to must use PM HSS to make raw material ability overtake international level in bottom of this kind of situation. Accordingly, establish international the concept of level of high grade cutting tool, do away with old thinking to already became urgent matter. CNC Milling CNC Machining