Background
The titanium alloy is an alloy formed by adding other elements into titanium as a base, wherein the TC11 titanium alloy is taken as a martensite (alpha + beta) two-phase heat strong titanium alloy with high aluminum equivalent, and has the advantages of small density, high specific strength, strong corrosion resistance and the like, and also has good high-temperature strength, thermal stability and creep resistance. The high-strength high-temperature-resistant high-strength high.
The forging method of die forging is adopted, the forged pieces in various shapes can be obtained, compared with a steel die forged piece, the die forging of titanium alloy is relatively difficult, because the deformation resistance of the titanium alloy at high temperature is larger than that of the steel piece, meanwhile, when the titanium alloy is contacted with hydrocarbon such as oil and the like in the heating, pickling and die forging processes, the titanium alloy is easily polluted by hydrogen, nitrogen and oxygen, the thermal deformation temperature of the titanium alloy is narrow, the metal fluidity is poor, the die is easily adhered, and if the die and the production process are improperly designed, the quality defects of local insufficient and folding of the forged piece are easily caused. Therefore, for some titanium alloy die forging pieces with complex shapes and special quality requirements, the design and production process of the die must be properly controlled, and titanium alloy die forging products with good quality can be obtained.
Patent document No. CN101722259A discloses a method for manufacturing a TC11 titanium alloy die forging bracket for an aircraft, which is to manufacture a die for the die forging bracket by using die machining technologies such as computer 3D die making and computer 3D die development and design, and manufacture the TC11 titanium alloy die forging bracket for the aircraft by using the steps of die forging hammer primary forging, die forging hammer secondary forging, double annealing treatment and the like. The method is characterized in that a die is manufactured firstly and then forged, the shape of the required forged piece is complex, but the material discharging mode and the like are not explained and limited in the forging process, so that the local filling of the forged piece is easily insufficient, and the quality defect of the forged piece is caused.
Disclosure of Invention
The invention provides a processing method of a titanium alloy die forging for solving the problems.
The method is realized by the following technical scheme:
a processing method of a TC11 titanium alloy die forging comprises the following specific steps:
1. designing a parting surface: according to the requirement of an demander, only the surfaces 1, 2 and 3 of the product are machined surfaces, and the rest are non-machined surfaces. Therefore, although the product is a die forging which is symmetrically distributed along the A-A surface, if the A-A surface is selected as a die parting surface, the forming is easy, but in order to meet the requirement of a demand on a non-processing surface of the product, the A-A surface cannot be used as the die parting surface for straight and symmetrical die parting during the die design, so that the asymmetric curved surfaces a-b-c are selected as the die parting surface for die parting, and the die drawing angle is 5 degrees;
2. forging forming finite element simulation analysis: adopting DEFORM-3D finite element analysis software to perform simulation analysis, wherein the forging weight of the forge piece is 0.88kg, and setting simulation basic parameters as follows: the specification of the blank is phi 70 multiplied by 90mm, the weight of the material is 1.55kg, the temperature of the blank is 980 ℃, the number of grids is 40000, the friction coefficient is 0.3, and the pressing rate of the upper die is 7 mm/s;
3. and (3) simulation result analysis: the 630t friction press is adopted for die forging forming production, and analysis is carried out on the forging forming demonstration process of the forge piece and a time-pressure curve graph of the upper die, so that the distribution of all parts of the blank is uniform and reasonable, when the pressure value basically reaches the upper pressure limit of the press, the blank is basically formed, in the forming process of the blank, the quality defects of folding, meat deficiency and the like do not occur on the blank body, the forming process of the forge piece is good, but the rough edge of the forge piece is large after forming, corresponding refinement can be carried out, and the material consumption of raw materials is reduced; it can be seen from the equivalent strain distribution diagram and the typical part time-strain curve diagram that the strain parts on the forging body are mainly concentrated at the connecting part of the horizontal cylinder and the vertical cylinder of the forging and the part near the burr discharge hole in the forging process, and the equivalent strains of the upper half part of the horizontal cylinder and the lower half part of the vertical cylinder are relatively small. The local minimum strain value of the forging is 0.26, the local maximum strain value is 2.58, the whole equivalent strain is mostly in the range of 0.417-1.04, the corresponding deformation is 34% -64.7%, the requirement of the deformation during titanium alloy forging can be met, and the structure and the performance of the forging can meet the requirement of a requirement; according to the forging streamline distribution diagram, the forging body streamline subjected to die forging according to the process scheme is basically distributed along the forging shape, the streamline is not obviously cut off, and the obvious flow penetration and vortex are avoided, so that the requirement of the low-power streamline of the forging of GJB 2744A is met;
4. forging: according to the simulation analysis result, adjusting the actual forging parameters as follows: the method comprises the following steps of reducing the weight of a blank to phi 70 x 75mm, weighing 1.29kg, keeping the temperature of the blank at 980 ℃, grid number 40000, friction coefficient 0.3, and pressing down speed of an upper die at 7-10mm/s, obliquely discharging the blank, and obtaining the forging after blanking, chamfering, turning end face, spraying lubricant, carrying out primary heating, making a rough shape, carrying out primary die pressing, carrying out hot trimming, spraying lubricant, carrying out secondary heating, carrying out secondary die pressing, carrying out hot trimming, blowing sand, carrying out double annealing, pickling, physicochemical treatment and acceptance inspection. Wherein the primary heating and the secondary heating are both at (T)β-35) deg.c; the primary die pressing and the secondary die pressing are both performed by adopting a friction press machine at the pressure of 6.3 MN; in the double annealing, the heating temperature of the first annealing is850 ℃ and 980 ℃, and the second annealing heating temperature is 530 ℃ and 580 ℃.
In conclusion, the beneficial effects of the invention are as follows: according to the invention, the TC11 titanium alloy die forging is forged by adopting an asymmetric curve die parting mode and different discharging modes, so that the material utilization rate reaches 68.3%, the integral deformation of the forging is basically within the range of 34-64.7%, the cavity in the die is well filled, and no obvious surface defect appears on the surface of the forging.
According to the requirement of the requirement, only the surface 1, the surface 2 and the surface 3 of the TC11 die forging 03-1 are machined surfaces, and the rest are non-machined surfaces, so that although the product is a die forging which is symmetrically distributed along the A-A surface, if the A-A surface is selected as the parting surface, the product can be easily formed, in order to meet the requirement of the requirement on the non-machined surfaces of the product, the A-A surface cannot be used as the parting surface for straight and symmetrical parting in the design of the die, and the requirement can be met only by machining the two machined surfaces of the surface 1 and the surface 2 in the subsequent machining process by adopting the forging mode of asymmetrical curve parting, so that the required size of the forging can be achieved, and the requirement on the non-machined surfaces of the product can be met. Because the forging mode of curved surface asymmetric parting is adopted, the end face of the lower die is a non-flat plane, so the blank can not adopt the discharging mode of horizontal discharging, and if the discharging mode of vertical discharging is adopted, the blank is concentrated on the vertical cavity part of the lower die to cause the excessive accumulation of the blank at the vertical cavity part of the lower die, and the horizontal cavity part causes the partial underfilling due to the shortage of the material, therefore, the forging mode of oblique discharging is adopted, and the quality problem of the partial underfilling of the forging can be avoided. The strength, plasticity and toughness of the forged piece obtained by the scheme can all meet the requirements of GJB 2744A, the microstructure of the forged piece is a typical two-state structure (equiaxed alpha + strip-shaped beta turns), the primary alpha content is about 35%, and the structure form meets the standard requirements. The streamline is basically consistent with the simulation result, no defect and clear crystal are seen, and the standard requirement is met. The processing requirement of a non-processing curved surface of a complex external die forging can be met by adopting a reasonable die splitting mode, the TC11 titanium alloy die forging is produced by adopting the process scheme, the utilization rate of raw materials can reach 68.3%, the integral deformation of the forging is basically within the range of 34-64.7%, a cavity in a die is well filled, no obvious surface defect appears on the surface of the forging, and the tissue and the performance of the obtained forging can reach the expected requirement. And, before actual forging, DEFORM-3D finite element analysis software is adopted for simulation analysis, so that the forging forming condition can be effectively predicted, the optimal process parameters are screened out, actual screening is not needed, and material waste caused by screening experiments is greatly reduced.
Detailed Description
The following is a detailed description of the embodiments of the present invention, but the present invention is not limited to these embodiments, and any modifications or substitutions in the basic spirit of the embodiments are included in the scope of the present invention as claimed in the claims.
Example 1
A processing method of a TC11 titanium alloy die forging comprises the following specific steps:
1. designing a parting surface: according to the requirement of an demander, only the surfaces 1, 2 and 3 of the product are machined surfaces, and the rest are non-machined surfaces. Therefore, although the product is a die forging which is symmetrically distributed along the A-A surface, if the A-A surface is selected as a die parting surface, the forming is easy, but in order to meet the requirement of a demand on a non-processing surface of the product, the A-A surface cannot be used as the die parting surface for straight and symmetrical die parting during the die design, so that the asymmetric curved surfaces a-b-c are selected as the die parting surface for die parting, and the die drawing angle is 5 degrees;
2. forging forming finite element simulation analysis: adopting DEFORM-3D finite element analysis software to perform simulation analysis, wherein the forging weight of the forge piece is 0.88kg, and setting simulation basic parameters as follows: the specification of the blank is phi 70 multiplied by 90mm, the weight of the material is 1.55kg, the temperature of the blank is 980 ℃, the number of grids is 40000, the friction coefficient is 0.3, and the pressing rate of the upper die is 7 mm/s;
3. and (3) simulation result analysis: the 630t friction press is adopted for die forging forming production, and analysis is carried out on the forging forming demonstration process of the forge piece and a time-pressure curve graph of the upper die, so that the distribution of all parts of the blank is uniform and reasonable, when the pressure value basically reaches the upper pressure limit of the press, the blank is basically formed, in the forming process of the blank, the quality defects of folding, meat deficiency and the like do not occur on the blank body, the forming process of the forge piece is good, but the rough edge of the forge piece is large after forming, corresponding refinement can be carried out, and the material consumption of raw materials is reduced; it can be seen from the equivalent strain distribution diagram and the typical part time-strain curve diagram that the strain parts on the forging body are mainly concentrated at the connecting part of the horizontal cylinder and the vertical cylinder of the forging and the part near the burr discharge hole in the forging process, and the equivalent strains of the upper half part of the horizontal cylinder and the lower half part of the vertical cylinder are relatively small. The local minimum strain value of the forging is 0.26, the local maximum strain value is 2.58, the whole equivalent strain is mostly in the range of 0.417-1.04, the corresponding deformation is 34% -64.7%, the requirement of the deformation during titanium alloy forging can be met, and the structure and the performance of the forging can meet the requirement of a requirement; according to the forging streamline distribution diagram, the forging body streamline subjected to die forging according to the process scheme is basically distributed along the forging shape, the streamline is not obviously cut off, and the obvious flow penetration and vortex are avoided, so that the requirement of the low-power streamline of the forging of GJB 2744A is met;
4. forging: according to the simulation analysis result, adjusting the actual forging parameters as follows: the method comprises the following steps of reducing the weight of a blank to phi 70 x 75mm, weighing 1.29kg, controlling the temperature of the blank to 980 ℃, the number of grids to 40000, the friction coefficient to 0.3, and the pressing rate of an upper die to 7mm/s, obliquely discharging the blank, and obtaining the forged piece after blanking, chamfering, turning the end face, spraying a lubricant, carrying out primary heating, manufacturing a rough shape, carrying out primary die pressing, carrying out hot trimming, spraying the lubricant, carrying out secondary heating, carrying out secondary die pressing, carrying out hot trimming, blowing sand, carrying out double annealing, carrying out acid washing, physicochemical treatment and acceptance. Wherein the temperature of the primary heating and the secondary heating is (T beta-35) DEG C; the primary die pressing and the secondary die pressing are both performed by adopting a friction press machine at the pressure of 6.3 MN; during double annealing, the first annealing heating temperature is 900 ℃, and the second annealing heating temperature is 550 ℃.
Example 2
A processing method of a TC11 titanium alloy die forging comprises the following specific steps:
1. designing a parting surface: according to the requirement of an demander, only the surfaces 1, 2 and 3 of the product are machined surfaces, and the rest are non-machined surfaces. Therefore, although the product is a die forging which is symmetrically distributed along the A-A surface, if the A-A surface is selected as a die parting surface, the forming is easy, but in order to meet the requirement of a demand on a non-processing surface of the product, the A-A surface cannot be used as the die parting surface for straight and symmetrical die parting during the die design, so that the asymmetric curved surfaces a-b-c are selected as the die parting surface for die parting, and the die drawing angle is 5 degrees;
2. forging forming finite element simulation analysis: adopting DEFORM-3D finite element analysis software to perform simulation analysis, wherein the forging weight of the forge piece is 0.88kg, and setting simulation basic parameters as follows: the specification of the blank is phi 70 multiplied by 90mm, the weight of the material is 1.55kg, the temperature of the blank is 980 ℃, the number of grids is 40000, the friction coefficient is 0.3, and the pressing rate of the upper die is 7 mm/s;
3. and (3) simulation result analysis: the 630t friction press is adopted for die forging forming production, and analysis is carried out on the forging forming demonstration process of the forge piece and a time-pressure curve graph of the upper die, so that the distribution of all parts of the blank is uniform and reasonable, when the pressure value basically reaches the upper pressure limit of the press, the blank is basically formed, in the forming process of the blank, the quality defects of folding, meat deficiency and the like do not occur on the blank body, the forming process of the forge piece is good, but the rough edge of the forge piece is large after forming, corresponding refinement can be carried out, and the material consumption of raw materials is reduced; it can be seen from the equivalent strain distribution diagram and the typical part time-strain curve diagram that the strain parts on the forging body are mainly concentrated at the connecting part of the horizontal cylinder and the vertical cylinder of the forging and the part near the burr discharge hole in the forging process, and the equivalent strains of the upper half part of the horizontal cylinder and the lower half part of the vertical cylinder are relatively small. The local minimum strain value of the forging is 0.26, the local maximum strain value is 2.58, the whole equivalent strain is mostly in the range of 0.417-1.04, the corresponding deformation is 34% -64.7%, the requirement of the deformation during titanium alloy forging can be met, and the structure and the performance of the forging can meet the requirement of a requirement; according to the forging streamline distribution diagram, the forging body streamline subjected to die forging according to the process scheme is basically distributed along the forging shape, the streamline is not obviously cut off, and the obvious flow penetration and vortex are avoided, so that the requirement of the low-power streamline of the forging of GJB 2744A is met;
4. forging: according to the simulation analysis result, adjusting the actual forging parameters as follows: the weight of the blank is reduced to phi 70 multiplied by 75mm, the weight of the blank is 1.29kg, the temperature of the blank is 980 ℃, the number of grids is 40000, the friction coefficient is 0.3, the pressing rate of an upper die is 9mm/s, the blank is subjected to oblique discharging in a mode of blanking, chamfering, end face turning, lubricant spraying, primary heating, primary die pressing, hot edge cutting, lubricant spraying, secondary heating, secondary die pressing, hot edge cutting, sand blowing, double annealing, acid washing, physicochemical treatment and acceptance to obtain the forged piece. Wherein the temperature of the primary heating and the secondary heating is (T beta-35) DEG C; the primary die pressing and the secondary die pressing are both performed by adopting a friction press machine at the pressure of 6.3 MN; when double annealing is carried out, the first annealing heating temperature is 980 ℃, and the second annealing heating temperature is 580 ℃.
Example 3
A processing method of a TC11 titanium alloy die forging comprises the following specific steps:
1. designing a parting surface: according to the requirement of an demander, only the surfaces 1, 2 and 3 of the product are machined surfaces, and the rest are non-machined surfaces. Therefore, although the product is a die forging which is symmetrically distributed along the A-A surface, if the A-A surface is selected as a die parting surface, the forming is easy, but in order to meet the requirement of a demand on a non-processing surface of the product, the A-A surface cannot be used as the die parting surface for straight and symmetrical die parting during the die design, so that the asymmetric curved surfaces a-b-c are selected as the die parting surface for die parting, and the die drawing angle is 5 degrees;
2. forging forming finite element simulation analysis: adopting DEFORM-3D finite element analysis software to perform simulation analysis, wherein the forging weight of the forge piece is 0.88kg, and setting simulation basic parameters as follows: the specification of the blank is phi 70 multiplied by 90mm, the weight of the material is 1.55kg, the temperature of the blank is 980 ℃, the number of grids is 40000, the friction coefficient is 0.3, and the pressing rate of the upper die is 7 mm/s;
3. and (3) simulation result analysis: the 630t friction press is adopted for die forging forming production, and analysis is carried out on the forging forming demonstration process of the forge piece and a time-pressure curve graph of the upper die, so that the distribution of all parts of the blank is uniform and reasonable, when the pressure value basically reaches the upper pressure limit of the press, the blank is basically formed, in the forming process of the blank, the quality defects of folding, meat deficiency and the like do not occur on the blank body, the forming process of the forge piece is good, but the rough edge of the forge piece is large after forming, corresponding refinement can be carried out, and the material consumption of raw materials is reduced; it can be seen from the equivalent strain distribution diagram and the typical part time-strain curve diagram that the strain parts on the forging body are mainly concentrated at the connecting part of the horizontal cylinder and the vertical cylinder of the forging and the part near the burr discharge hole in the forging process, and the equivalent strains of the upper half part of the horizontal cylinder and the lower half part of the vertical cylinder are relatively small. The local minimum strain value of the forging is 0.26, the local maximum strain value is 2.58, the whole equivalent strain is mostly in the range of 0.417-1.04, the corresponding deformation is 34% -64.7%, the requirement of the deformation during titanium alloy forging can be met, and the structure and the performance of the forging can meet the requirement of a requirement; according to the forging streamline distribution diagram, the forging body streamline subjected to die forging according to the process scheme is basically distributed along the forging shape, the streamline is not obviously cut off, and the obvious flow penetration and vortex are avoided, so that the requirement of the low-power streamline of the forging of GJB 2744A is met;
4. forging: according to the simulation analysis result, adjusting the actual forging parameters as follows: the method comprises the steps of reducing the weight of a blank to phi 70 x 75mm, weighing 1.29kg, controlling the temperature of the blank to 980 ℃, the number of grids to 40000, the friction coefficient to 0.3 and the pressing rate of an upper die to 7-10mm/s, obliquely discharging the blank, and obtaining the forged piece after blanking, chamfering, turning the end face, spraying a lubricant, carrying out primary heating, carrying out primary die pressing, carrying out hot edge cutting, spraying a lubricant, carrying out secondary heating, carrying out secondary die pressing, carrying out hot edge cutting, blowing sand, carrying out double annealing, carrying out acid washing, carrying out physicochemical treatment and acceptance. Wherein the temperature of the primary heating and the secondary heating is (T beta-35) DEG C; the primary die pressing and the secondary die pressing are both performed by adopting a friction press machine at the pressure of 6.3 MN; during double annealing, the first annealing heating temperature is 850 ℃, and the second annealing heating temperature is 530 ℃.
Physical and chemical properties of primary and 03-1 forgings
The TC11 die forging 03-1 obtained in example 1 was subjected to a performance test, and the results are shown in table 1.
TABLE 1 conventional Performance results (Long transverse)
Note: l1 and L2 are 2 specimens cut out from the same test material.