CN106391958A

CN106391958A - Method for manufacturing TC4 large-sized titanium alloy inclined tube-type die forged piece

Info

Publication number: CN106391958A
Application number: CN201510483477.4A
Authority: CN
Inventors: 陈文杰
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-07-31
Filing date: 2015-07-31
Publication date: 2017-02-15

Abstract

The invention discloses a method for manufacturing a TC4 large-sized titanium alloy inclined tube-type die forged piece with the high structure property level. The manufacturing method includes the steps that a TC4 large-sized titanium alloy bar is sequentially subjected to cake upsetting, straight hole punching and straight hole broaching treatment; after straight hole broaching, inclined hole broaching is performed to complete waste billet forming manufacture; and at last, a waste billet is subjected to multi-heating number die forging forming. By the adoption of the method, after the TC4 large-sized titanium alloy bar is sequentially subjected to cake upsetting, straight hole punching and straight hole broaching treatment, no circular rolling forming is required, instead, inclined hole broaching is performed to complete waste billet forming manufacture, and finally the waste billet is subjected to multi-heating number die forging forming, so that high structure inhomogeneity of the forged piece is effectively prevented. Moreover, die forging press force is high, and therefore the grain refinement degree is high, original large grains can be crushed thoroughly, and the structure property and ultrasonic flaw detection level of the TC4 large-sized titanium alloy inclined tube-type die forged piece manufactured through the method at last can be made high. The method is suitable for being applied and popularized in the technical field of alloy forging.

Description

The manufacture method of TC4 large titanium alloy oblique cylinder class forging part

Technical field

The present invention relates to alloy forging technical field, the manufacture method of the oblique cylinder class forging part of especially a kind of TC4 large titanium alloy.

Background technology

The nominal composition of TC4 titanium alloy is Ti-6Al-4V, is moderate strength alpha and beta type titan alloy, and annealed structure is alpha+beta phase. TC4 is most popular alloy at present, has excellent combination property and hot-working character, and carrying out solid solution, to produce timeliness strong Change, but through hardening section is usually no more than 25mm, mainly for the manufacture of the fan of electromotor, compressor disc and blade, and aircraft The main load-carrying member such as the beam in structural member, joint, bulkhead.

TC4 titanium alloy booster stage drum barrel forging part is the vitals needed for electromotor, and this forging shape belongs to large-scale oblique cylinder class Forging, inside/outside diameter size is big, deep-small hole thin-walled, forming difficulty, and the forging hitting power of needs is larger, and structure property requires High.The method typically adopting cerclage with the manufacture method of booster stage drum barrel forging currently for electromotor, the method produces drum barrel The main step of forging：Upsetting cake → punching → reaming → looping mill rolling shapes.Because looping mill rolling process is the process of blank local deformation, should Process creates larger structural heterogenity；And looping mill rolling deflection is less, and for nipping deformation (as local deformation), roll Power processed is much smaller compared with die forging press power, so its degree of grain refinement is not, original big crystal grain crushes not thorough.So, ring Roll produce electromotor drum barrel forging structure property and ultrasonic examination level relatively low it is impossible to reach correlation technical standard.

Content of the invention

The technical problem to be solved is the TC4 large titanium alloy oblique cylinder class providing a kind of forging structure property level higher The manufacture method of forging part.

The technical solution adopted for the present invention to solve the technical problems is：The manufacturer of this TC4 large titanium alloy oblique cylinder class forging part Method, including TC4 titanium alloy large size bar being carried out successively with upsetting cake, rushing straight hole, expand straight hole process, expands straight hole and followed by carries out Expand inclined hole and complete waste base molding manufacture, finally waste base is carried out with many fire time die-forging formings.

It is further that, during the fire time die-forging forming how, deformation temperature controls between β -40 DEG C～β -20 DEG C.

It is further that, during the fire time die-forging forming how, often fiery deflection is 5%～80%.

It is further that, during the fire time die-forging forming how, often fiery deflection is 10%.

It is further, during the fire time die-forging forming how, often by the way of air cooling, forging to be cooled down after fire deformation.

The invention has the beneficial effects as follows：The present invention is carrying out upsetting cake successively, is rushing straight hole, expands directly to TC4 titanium alloy large size bar Hole does not carry out cerclage shaping after processing but then carries out expansion inclined hole and complete waste base molding manufacture, and finally waste base is carried out with many fire time moulds It is swaged into shape, forging can be prevented effectively from and produce larger structural heterogenity；And die forging press power is larger, so its crystal grain is thin Change degree is higher, and original big crystal grain can be made to crush thoroughly, so that the TC4 large titanium alloy oblique cylinder class mould finally producing Forging structure property and ultrasonic examination level are higher.

Specific embodiment

The invention will be further described below.

The manufacture method of this TC4 large titanium alloy oblique cylinder class forging part, carries out upsetting successively including to TC4 titanium alloy large size bar Cake, rush straight hole, expand straight hole process, expand straight hole followed by carry out expand inclined hole complete waste base molding manufacture, finally waste base is carried out many Fire time die-forging forming.The present invention is carrying out upsetting cake successively, is rushing straight hole, expands after straight hole is processed not to TC4 titanium alloy large size bar Carry out cerclage shaping but then carry out expansion inclined hole and complete waste base molding manufacture, finally waste base is carried out with many fire time die-forging formings, can Produce larger structural heterogenity to be prevented effectively from forging；And die forging press power is larger, so its degree of grain refinement is higher, Original big crystal grain can be made to crush thoroughly, so that the TC4 large titanium alloy oblique cylinder class forging part structure property finally producing Higher with ultrasonic examination level.

Pointed out according to related data, the forging temperature of TC4 titanium alloy is 940 DEG C～990 DEG C, alloy phase change o'clock at 1000 DEG C about, β is the transformation temperature of alloy, during the fire time die-forging forming how, within during heating, furnace temperature fluctuation controls ± 5 DEG C, mold tooling 300～350 DEG C of preheating temperature, heat time heating time is 100～250 minutes.

Because processing parameters are larger on the microstructure impact of TC4 titanium alloy, during the deformation of alpha+beta area, obtain equiaxed structure；Phase During with deflection, the volume fraction with the reduction primary alpha phase of temperature dramatically increases, therefore, in order to obtain preferable microstructure, During the fire time die-forging forming how, deformation temperature controls between β -40 DEG C～β -20 DEG C.

Under identical deformation temperature, with the increase of deflection, the volume fraction change of primary alpha phase is inconspicuous, is increased slightly, But there is obvious directivity, elongate along the direction vertical with Impact direction, therefore, during how fire time die-forging forming, often Fiery deflection can be 5%～80%, but it is contemplated that primary alpha phase obtains directional change, often fiery deflection is unsuitable excessive, because This, during the fire time die-forging forming how, often fiery deflection is preferably 10%.

In addition, in order that the forging performance that finally obtains more preferably, during how fire time die-forging forming, often adopts after fire deformation The mode of air cooling cools down to forging.

Following table is to be closed using the TC4 Large Titanium that the manufacture method of TC4 large titanium alloy of the present invention oblique cylinder class forging part is made The performance parameter of the oblique cylinder class forging part of gold：

Table 1 room-temperature mechanical property

Table 2 room temperature low-cycle fatigue

Can be evident that from table 1, table 2, using the manufacturer of TC4 large titanium alloy of the present invention oblique cylinder class forging part TC4 large titanium alloy oblique cylinder its mechanical property of class forging part that method produces and cycle life are above technical standard, Ke Yiman The related technical requirements of foot.

Claims

The manufacture method of 1.TC4 large titanium alloy oblique cylinder class forging part, carries out upsetting successively including to TC4 titanium alloy large size bar Cake, rush straight hole, expand straight hole process it is characterised in that：Expansion straight hole followed by carries out expansion inclined hole and completes waste base molding manufacture, finally Waste base is carried out with many fire time die-forging formings.
2. the oblique cylinder class forging part of TC4 large titanium alloy as claimed in claim 1 manufacture method it is characterised in that：How fiery During secondary die-forging forming, deformation temperature controls between β -40 DEG C～β -20 DEG C.
3. the oblique cylinder class forging part of TC4 large titanium alloy as claimed in claim 2 manufacture method it is characterised in that：How fiery During secondary die-forging forming, often fiery deflection is 5%～80%.
4. the oblique cylinder class forging part of TC4 large titanium alloy as claimed in claim 3 manufacture method it is characterised in that：How fiery During secondary die-forging forming, often fiery deflection is 10%.
5. the manufacture of the TC4 large titanium alloy oblique cylinder class forging part according to any one claim in Claims 1-4 Method it is characterised in that：During the fire time die-forging forming how, often forging is carried out cold after fire deformation by the way of air cooling But.