CN104690198A - Forming method of large GH4169 alloy direct aging disc forging - Google Patents

Abstract

The invention discloses a technology of 'die forging for blank forming plus die forging for forming plus direct aging' for the forming problem of the large GH4169 alloy direct aging disc forging. Since the traditional 'free forging for blank forming' is changed into the 'die forging for blank forming', uncontrollable factors of larger heating number and deformation in a free forging procedure are eliminated; the control of heating and the deformation in a forging technology are guaranteed; a forging after final direct aging treatment can stably meet requirements of a level ten grain size; the production efficiency is improved; and the cost is lowered.

Description

A kind of forming method of large-scale GH4169 alloy direct aging dish forging

Technical field:

The present invention relates to the method for forging and molding of large-scale GH4169 alloy direct aging dish forging part, particularly projected area is greater than 0.2m ²and grain size requires the disk forge piece of 10 grades.

Background technology:

GH4169 alloy is a kind of with the nickel base superalloy of the γ ＂ of body-centered tetragonal and face-centred cubic γ ＇ phase precipitation strength, be mainly used in the crucial load part of Aero-Space equipment, when these crucial load parts manufacture, forging used has very high requirement to performance, for the crucial load part at some engine core position, require that the grain size after the complete heat treatment of GH4169 alloy forging reaches 10 grades, and conventional forged after, solid-solution and aging heat treatment does not almost reach the grain size requirement of 10 grades, even if adopt direct aging Technology for Heating Processing, also the open die forging base moderate heat due to routine is secondary more, the uncontrollable reason of deflection and cause technique instability (key of grain refinement is the control to heating and deflection in Forging Technology, and open die forging is difficult to control), therefore according to the technique of traditional " open die forging base+die-forging forming+direct aging ", end product quality is unstable, can not be stable reach 10 grades of grain size requirements.

Traditional GH4169 alloy disc class takes the mode of " open die forging base+die forging " to complete at direct aging forging part before treatment, usually following two kinds of typical process route: Yi Zhongshi are had: upsetting cake → punching → horse expansion → reaming (ring base) → die forging, this technique due to Forging Technology link and fire time more, and horse is expanded the repeatedly small deformation of process and can cause the uneven of blank tissue, more difficultly reach more than the 8 grades grain size requirements of ring base.The second is: upsetting cake → punching → reaming (ring base) → die forging, and this scheme advantage eliminates horse to expand operation, raises the efficiency, and that simultaneously improves ring base due to the increase of reaming link deflection organizes level; Shortcoming is that after removing horse expansion, add the difficulty of reaming, namely reaming one fire completes the deflection of more than 40%, and capacity of equipment requires higher, and the operability of technique needs to consider; Above two kinds of process programs, owing to relating to free forging process, are affected by human factors comparatively large, unstable product quality, therefore are difficult to meet forging ' s block dimension and integrative organization's performance requirement.

The invention discloses the technique of one " die forging base+die-forging forming+direct aging ", by traditional " open die forging base " is changed into " die forging base ", eliminate open die forging operation moderate heat secondary more, the uncontrollable factor of deflection, ensure that the control to heating and deflection in Forging Technology, ensure that the forging after final direct aging process can stablize the grain size requirement reaching 10 grades, improve production efficiency, reduce cost.

Technical problem of the present invention is:

For the forging molding of large-scale GH4169 alloy direct aging dish forging part, according to the technique of traditional " open die forging base+die-forging forming+direct aging ", end product quality is unstable, can not be stable reach 10 grades of grain size requirements.

Technical scheme:

Step 1 prefabricated blank, is adopted the mode of die-forging forming to complete upsetting cake and punching operation, by mould controlling distortion amount between 50% to 55%, is added remove punching core material by machine, improve ring base size and metallurgical quality uniformity;

Step 2 preformed, adopts the swollen hole of die forging to complete reaming operation, by mould controlling distortion amount between 20% to 25%;

Step 3 die-forging forming, utilizes finish-forging die one pyrogene type, by mould controlling distortion amount between 30% to 35%;

In 30s, enter water after step 4 die forging final molding, be chilled to room temperature, complete direct aging process.

The invention has the beneficial effects as follows:

Adopt die-forging forming to replace open die forging upsetting cake, punching, improve technology stability; Adopt the swollen hole of die forging to replace looping mill rolling, reasonable distribution and controlling distortion amount, improve ring base performance;

On the whole, by traditional " open die forging base " is changed into " die forging base ", eliminate open die forging operation moderate heat secondary more, the uncontrollable factor of deflection, ensure that the control to heating and deflection in Forging Technology, ensure that the forging after final direct aging process can stablize the grain size requirement reaching 10 grades, improve production efficiency, reduce manufacturing cost.

Concrete case embodiment

Below with reference to embodiment, technical solution of the present invention is further described:

Large-scale GH4169 alloy direct aging dish forging of the present invention, external diameter φ 681mm, internal diameter φ 374mm, projected area is about 0.25m ², all round properties index of forging and grain size require the requirement (grain size requires 10 grades) that should meet xx-0515 standard.

Its forging step is as follows in detail:

The pattern of first step design upsetting cake, increase drift in the centre up and down of pattern, directly put in pattern by bar, hammering, to certain height, makes blank just be full of die cavity (not going out burr), completes prefabricated blank shaping.

The web portion extension set at prefabricated blank center adds to fall by the mode that second step is added by machine, so far realizes upsetting cake in traditional handicraft, work that punching two operations will complete, and this operation deflection reaches more than 50%, and grain size can improve 2 ~ 2.5 grades.

3rd step design preforming tool, the counterdie of this mould has the fuse of a taper, fuse has two kinds of gradients, top is 15 degree, and below is 10 degree, and object comes swollen hole by the gradient of taper fuse, realize the work that traditional reaming operation will complete, this operation deflection is less, by mould controlling distortion amount between 20% to 25%, mainly makes crystal grain no longer grow up.

After 4th step completes preforming operation, finish-forging die die cavity directly put into by waste base, completes die forging final molding, and this operation deflection reaches more than 30%, crystal grain energy refinement 1 ~ 1.5 grade.

In 30s, enter water after 5th step die forging final molding, be chilled to room temperature, complete direct aging process.

The homogeneous fire of forging process of this technique completes, and is meeting on the shaping basis of forging, after tested, finally can stablize the microscopic structure (10 grades of grain sizes) being met standard-required.

Claims (1)

1. a forming method for large-scale GH4169 alloy direct aging dish forging, is characterized in that, comprise the steps,

Step 1 prefabricated blank, is adopted the mode of die-forging forming to complete upsetting cake and punching operation, by mould controlling distortion amount between 50% to 55%, is added remove punching core material by machine, improve ring base size and metallurgical quality uniformity;

Step 2 preformed, adopts the swollen hole of die forging to complete reaming operation, by mould controlling distortion amount between 20% to 25%;

Step 3 die-forging forming, utilizes finish-forging die one pyrogene type, by mould controlling distortion amount between 30% to 35%;

In 30s, enter water after step 4 die forging final molding, be chilled to room temperature, complete direct aging process.