GH4169 alloy integral blade ring forging rolling forming and forging metallurgy quality evaluation method

Abstract

The invention relates to a GH4169 alloy integral blade ring forging rolling forming and forging metallurgy quality evaluation method, which is characterized by comprising the following steps of: firstly, determining the shape and the size of a forging according to a part drawing, and determining the specification and the size of a GH4169 alloy bar through theoretical calculation; based on the final deformation amount and deformation temperature control, forming process design is conducted, and finite element simulation verification is conducted; forge piece trial-manufacturing is conducted according to the process scheme, and acceptance inspection is conducted through the metallurgy quality evaluation method; the GH4169 integral blade ring forge piece can meet the application requirement of an aero-engine for the GH4169 integral blade ring forge piece. Firstly, according to a part drawing, the shape and the size of a forge piece are determined, and the specification and the size of a GH4169 alloy bar are determined through theoretical calculation. And based on the final deformation amount and deformation temperature control, forming process design is carried out, and finite element simulation verification is carried out.

Description

Technical Field

[0001] The invention relates to the technical field of manufacturing integral blade ring forgings for aircraft engines, and in particular to a method for rolling and forming GH4169 alloy integral blade ring forgings and a method for evaluating the metallurgical quality of the forgings. Background Art

[0002] In order to further reduce the structural weight of aircraft engines and improve the thrust-to-weight ratio and comprehensive performance of aircraft engines, GH4169 integral blade rings have begun to be used in aircraft engines. For this type of new ring + blade structure forgings, the forming method has also been changed from ring rolling and blade die forging to integral rolling of blade ring forgings. Therefore, considering that the integral blade ring forgings must take into account the organization and mechanical properties of both the ring and blade parts, the current GH4169 alloy ordinary ring rolling process obviously cannot meet the requirements. It is necessary to develop a process suitable for integral rolling of blade ring forgings, optimize the distribution of deformation per pass and deformation temperature, so that it matches the organization and performance requirements of blade ring forgings.

[0003] In addition to the forming process, the current GH4169 alloy integral blade ring forgings also lack a dedicated metallurgical quality assessment method. They can only be accepted using the ordinary GH4169 alloy ring standard, mainly testing room temperature hardness, room temperature tensile, 650℃ high temperature tensile, 650℃ / 690MPa high temperature durability and high and low magnification structures. However, the above metallurgical quality assessment method has obvious drawbacks. The performance specimens of GH4169 alloy ring forgings are mainly cut along the chord direction, while the main mechanical properties of the blades are tested in the length direction, that is, the radial direction of the ring forging. Due to the existence of deformation streamlines caused by rolling, there may be certain differences in the mechanical properties of the forgings in different directions. Therefore, the metallurgical quality assessment method currently used cannot achieve complete control of the metallurgical quality of GH4169 integral blade ring forgings. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a method for rolling forming and metallurgical quality assessment of GH4169 alloy integral blade ring forgings; the specific technical scheme is as follows:

[0005] A GH4169 alloy integral blade ring forging rolling forming and forging metallurgical quality assessment method, firstly, according to the part drawing, the shape and size of the forging are determined, and the specification and size of the GH4169 alloy bar are determined by theoretical calculation; the forming process is designed based on the final deformation amount and deformation temperature control and finite element simulation verification is carried out; the forging is trial-produced according to the process plan, and the metallurgical quality assessment method is used for acceptance; the following steps are specifically included:

[0006] Step 1: Determine the GH4169 alloy integral leaf ring forging drawing

[0007] Determine the forging structure and size according to the GH4169 alloy integral blade ring parts design drawing;

[0008] Step 2: Determine the specifications of GH4169 alloy bars

[0009] According to the principle of constant volume, the weight of the bar material can be calculated. The volume V of the raw material bar can be approximately equal to the volume of the ring forging plus the volume of the punching core material:

[0010]

[0011] The weight of the rod is Where D0 and H0 are the diameter and height of the rod, respectively, and ρ is the density of GH4169 alloy;

[0012] Step 3: Design the forming process of GH4169 alloy integral blade ring forgings

[0013] The forging forming process route is upsetting → punching → hole expansion → rolling;

[0014] Step 4: Forming process simulation verification

[0015] In order to ensure the accuracy of the simulation results, a GH4169 alloy material database was built in the finite element simulation software, and a finite element simulation model for the integral blade ring rolling was constructed to simulate the rolling forming process, predict possible forging defects, and whether the final deformation and final rolling temperature can meet the process requirements;

[0016] Step 5: Trial production of GH4169 alloy integral blade ring forgings

[0017] The bar is heated to 1020℃ and then kept warm, and then upsetting and punching are performed; the bar is returned to the furnace and reheated to 1000℃, and the holding time is halved, and the ring blank is expanded and rolled to the size specified in the forging drawing, and then air-cooled to room temperature; and then the GH4169 alloy integral blade ring forging is heat treated;

[0018] Step 6: Metallurgical quality assessment of GH4169 alloy integral blade ring forgings

[0019] Samples were taken from the anatomical parts and tested for hardness, room temperature tensile strength, high temperature tensile strength, high temperature endurance, and high and low magnification tissue tests.

[0020] The method for rolling forming and metallurgical quality assessment of GH4169 alloy integral blade ring forgings is preferably implemented as follows: in step 1, since the integral blade ring is a new structure forging, in order to ensure that the forging can meet the subsequent machining requirements, the forging adopts a rectangular cross-section, and the single-side margin along the maximum outer dimension of the part is controlled at 10 to 15 mm, thereby obtaining the size of the integral blade ring forging, including the outer diameter D, the inner diameter d and the axial height H.

[0021] The method for rolling forming and metallurgical quality assessment of GH4169 alloy integral blade ring forgings is preferably implemented as follows: in step three, in order to ensure that the integral blade ring forging can take into account the performance of the ring part and the blade part, the deformation of the last rolling process is controlled within 15% to 40%; the deformation distribution of the preceding processes is determined in sequence according to the final deformation; in terms of rolling temperature, upsetting and punching are completed with one fire, the initial forging temperature is 1020°C, and the final rolling temperature is set to 1000°C to ensure performance.

[0022] Compared with the prior art, the present invention has the following beneficial technical effects:

[0023] The technical solution of the present invention can meet the application requirements of aero-engines for GH4169 integral blade ring forgings. First, according to the part drawing, the shape and size of the forging are determined, and the specifications and sizes of the GH4169 alloy bar are determined by theoretical calculation. The forming process design is carried out based on the final deformation amount and deformation temperature control, and finite element simulation verification is carried out. The forgings are trial-produced according to the process plan, and the acceptance is carried out according to the metallurgical quality assessment method proposed in the present invention. Finally, the matching of the standard technical indicators and the forming process is verified; the current GH4169 alloy integral blade ring forgings are not matched with the overall rolling process and the existing sampling direction cannot fully realize the metallurgical quality control of the forgings. Thereby achieving the improvement of the metallurgical quality control level of GH4169 alloy integral blade ring forgings, improving the quality reliability of the integral blade ring parts, and ensuring the flight safety of aero-engines. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Design technical implementation flow chart for simulation test pieces;

[0025] Figure 2 Schematic diagram of sampling the physical and chemical properties of the integral blade ring forging. DETAILED DESCRIPTION

[0026] The following is combined with Figure 1-2 The present invention is described in detail, but the protection scope of the present invention is not limited by the accompanying drawings.

[0027] A forming and metallurgical quality assessment method for GH4169 alloy integral blade ring forgings can meet the requirements for forming and acceptance of GH4169 alloy integral blade ring forgings for aircraft engines. To this end, the main technical solution of the present invention includes the following steps:

[0028] Step 1: Determine the GH4169 alloy integral leaf ring forging drawing. According to the GH4169 alloy integral leaf ring part design drawing, determine the forging structure and size. Since the integral leaf ring is a new structure forging, in order to ensure that the forging can meet the subsequent machining requirements, the forging adopts a rectangular cross-section, and the single-side margin along the maximum outer dimension of the part is controlled at 10-15mm, thereby obtaining the integral leaf ring forging size, including the outer diameter D, inner diameter d and axial height H.

[0029] Step 2: Determine the specifications of GH4169 alloy bars

[0030] According to the principle of constant volume, the weight of the bar material can be calculated. The volume V of the raw material bar can be approximately equal to the volume of the ring forging plus the volume of the punching core material:

[0031]

[0032] The weight of the rod is Where D0 and H0 are the diameter and height of the rod respectively, and ρ is the density of GH4169 alloy.

[0033] Step 3: Design the forming process of GH4169 alloy integral blade ring forgings

[0034] The forging forming process route is upsetting → punching → expansion → rolling. In order for the overall blade ring forging to take into account the performance of the ring part and the blade part, the deformation of the last rolling process should be controlled within 15% to 40%. The deformation distribution of the previous process is determined in sequence according to the final deformation. In terms of rolling temperature, upsetting and punching are completed with one fire, and the initial forging temperature is 1020℃. To ensure performance, the final rolling temperature is set to 1000℃.

[0035] Step 4: Forming process simulation verification

[0036] To ensure the accuracy of the simulation results, a GH4169 alloy material database was built in the finite element simulation software, and a finite element simulation model of the integral blade ring rolling was constructed to simulate the rolling forming process, predict possible forging defects, and whether the final deformation and final rolling temperature could meet the process requirements.

[0037] Step 5: Trial production of GH4169 alloy integral blade ring forgings

[0038] The bar is heated to 1020℃ and then kept warm, then upsetting and punching are performed; it is returned to the furnace and reheated to 1000℃, the holding time is halved, the ring blank is expanded and rolled to the size specified in the forging drawing, and air-cooled to room temperature. Then the GH4169 alloy integral blade ring forgings are heat treated.

[0039] Step 6: Metallurgical quality assessment of GH4169 alloy integral blade ring forgings. Samples were taken from the dissected parts to test hardness, room temperature tensile, high temperature tensile, high temperature durability, and high and low magnification structures. Figure 2 The specific detection is shown in Table 1.

[0040] Table 1 GH4169 integral blade ring metallurgical quality assessment plan

[0041]

[0042] Conclusion: The technical index requirements for room temperature tensile mechanical properties of chordal and radial specimens of GH4169 alloy integral blade ring forgings are: tensile strength σ b ≥1275MPa, yield strength σ 0.2 ≥1035MPa, elongation after fracture δ5≥12%, section shrinkage ψ≥15%;

[0043] The technical index requirements for the high temperature tensile mechanical properties of GH4169 alloy integral blade ring forgings at 650℃ for chordal and radial specimens are: tensile strength σ b ≥1000MPa, yield strengthσ 0.2 ≥860MPa, elongation after fracture δ5≥12%, section shrinkage ψ≥15%;

[0044] The technical index requirements for the endurance mechanical properties of GH4169 alloy integral blade ring forgings under 650℃ high temperature and 690MPa loading stress are: the duration of high temperature endurance fracture of the sample τ≥25h, and the elongation δ≥5%;

[0045] The hardness and high and low structure of GH4169 alloy integral blade ring forgings can be inspected and accepted according to the GH4169 common ring standard, specifically:

[0046] The technical index requirements for the hardness of GH4169 alloy integral blade ring forgings at room temperature are: HB = 346 ~ 450;

[0047] The macrostructure technical index requirements of GH4169 integral blade ring forgings are: there should be no visible metallurgical defects such as looseness, pinholes, cracks, shrinkage holes, segregation, slag inclusions, etc. on the transverse macroscale specimens cut from the forgings or test rings. At the same time, check for dark corrosion areas, white spots or shallow corrosion areas.

[0048] The requirements for the high-magnification microstructure technical indicators of GH4169 integral blade ring forgings are: cut transverse specimens from the forgings or test rings in the supplied state, and check the carbides, carbonitrides, δ phases, Laves phases and grain size, among which the grain size determination is carried out in accordance with GB / T 6394.

Claims

1. A method for rolling forming and metallurgical quality assessment of GH4169 alloy integral blade ring forgings, characterized in that: First, the shape and size of the forging are determined according to the part drawing, and the specifications and dimensions of the GH4169 alloy bar are determined through theoretical calculation; the forming process design is carried out based on the final deformation amount and deformation temperature control, and finite element simulation verification is carried out; the forging is trial-produced according to the process plan, and the metallurgical quality assessment method is used for acceptance; the specific steps include: Step 1: Determine the GH4169 alloy integral leaf ring forging drawing Determine the forging structure and size according to the GH4169 alloy integral blade ring parts design drawing; Step 2: Determine the specifications of GH4169 alloy bars According to the principle of constant volume, the weight of the bar material can be calculated. The volume V of the raw material bar can be approximately equal to the volume of the ring forging plus the volume of the punching core material: The weight of the rod is Where D0 and H0 are the diameter and height of the rod, respectively, and ρ is the density of GH4169 alloy; Step 3: Design the forming process of GH4169 alloy integral blade ring forgings The forging forming process route is upsetting → punching → hole expansion → rolling; Step 4: Forming process simulation verification In order to ensure the accuracy of the simulation results, a GH4169 alloy material database was built in the finite element simulation software, and a finite element simulation model for the integral blade ring rolling was constructed to simulate the rolling forming process, predict possible forging defects, and whether the final deformation and final rolling temperature can meet the process requirements; Step 5: Trial production of GH4169 alloy integral blade ring forgings The bar is heated to 1020℃ and then kept warm, and then upsetting and punching are performed; the bar is returned to the furnace and reheated to 1000℃, and the holding time is halved, and the ring blank is expanded and rolled to the size specified in the forging drawing, and then air-cooled to room temperature; and then the GH4169 alloy integral blade ring forging is heat treated; Step 6: Metallurgical quality assessment of GH4169 alloy integral blade ring forgings Samples were taken from the anatomical parts and tested for hardness, room temperature tensile strength, high temperature tensile strength, high temperature endurance, and high and low magnification tissue tests.

2. A GH4169 alloy integral blade ring forging rolling forming and forging metallurgical quality assessment method according to claim 1, characterized in that: In step one, since the integral leaf ring is a new structure forging, in order to ensure that the forging can meet the subsequent machining requirements, the forging adopts a rectangular cross-section, and the single-side allowance along the maximum outer dimension of the part is controlled at 10 to 15 mm, thereby obtaining the integral leaf ring forging size, including the outer diameter D, inner diameter d and axial height H.

3. The method for rolling forming and metallurgical quality assessment of GH4169 alloy integral blade ring forgings according to claim 1, characterized in that: In step three, in order to ensure that the overall blade ring forging can take into account the performance of both the ring part and the blade part, the deformation of the last rolling process is controlled at 15% to 40%; the deformation distribution of the previous processes is determined in sequence according to the final deformation; in terms of rolling temperature, upsetting and punching are completed with one fire, the initial forging temperature is 1020°C, and in order to ensure performance, the final rolling temperature is set to 1000°C.

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