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CN-117300323-B - Design method of explosion welding process parameters

CN117300323BCN 117300323 BCN117300323 BCN 117300323BCN-117300323-B

Abstract

The invention relates to a design method of explosion welding process parameters, belongs to the technical field of explosion welding, and solves the technical problem of reasonably determining the base coating interval and the medicine distribution thickness in the explosion welding process. A design method of explosion welding technological parameters comprises the following steps of 1, determining a base layer and a coating layer in explosion welding according to unit area mass of welding materials, arranging the base layer and the coating layer in parallel, 2, determining an optional range of collision point speed V c in explosion welding, 3, determining a minimum value V pmin of coating impact speed V p , determining a value range of collision angle theta, further determining specific values of collision angle theta, collision point speed V c and coating impact speed V p , 4, determining a distance A between the base layer and the coating layer based on a functional conservation principle, and 5, determining a medicine distribution thickness zeta based on a momentum conservation principle. The invention opens up a new path for determining the interval between base layers and the thickness of medicine distribution, and is more scientific than the existing empirical formula.

Inventors

  • WU FENGYONG
  • WANG BIN
  • YANG DOUDOU
  • Long Lianzhu
  • LI SHENG
  • GUO CHENGLONG
  • TIAN QICHAO

Assignees

  • 北京星航机电装备有限公司

Dates

Publication Date
20260508
Application Date
20230926

Claims (7)

  1. 1. A method for designing explosive welding process parameters, the method comprising the steps of: Step 1, determining a base layer and a coating layer in explosion welding according to the unit area quality of welding materials, and arranging the base layer and the coating layer in parallel; step 2, determining the optional range of the collision point speed V c during explosion welding according to the material parameters of the base layer and the coating layer; Step 3, determining welding energy required by welding according to material parameters of a base layer and a coating, taking kinetic energy of the coating as a welding energy source, determining a minimum value V pmin of a coating impact speed V p during explosion welding according to minimum welding energy requirements, determining a value range of an impact angle theta by referring to a fourth intensity theory and welding energy requirements, and further determining specific values of the impact angle theta, the impact point speed V c and the coating impact speed V p ; Step 4, determining a distance A between the base layer and the coating based on functional conservation according to the coating impact speed V p , the collision angle theta, the explosive explosion speed V d and the physical parameters of the coating and the explosive; Step 5, determining the drug distribution thickness zeta based on conservation of momentum according to the coating impact speed V p , the explosive explosion speed V d and the physical parameters of the coating and the explosive; In the step 3, the welding energy and the coating kinetic energy are in a direct proportion relation, and the minimum value V pmin between the lower limit of the welding energy and the coating impact speed V p is as follows: 1/2MV pmin 2 =E wmin =σ b SH f βδ Wherein M is the mass of the coating in kilograms, S is the area of the coating in square meters, rho f is the density of the coating in kilograms per cubic meter, H f is the thickness of the coating in meters, and 1/2MV pmin 2 is the minimum kinetic energy of the coating impact in joules; The method comprises the steps of converting the minimum kinetic energy of the coating impact into the welding energy, wherein E wmin is the lower limit of the welding energy, the unit is joule, sigma b is the tensile strength of the coating or the base material, the unit is pascal, beta is the proportion of the minimum welding layer thickness to the coating thickness H f , delta is the extensibility of the welding layer, and the unit is a percentage number and dimensionless; In the step 3, the stress failure criterion of the fourth strength theory is (σ 2 +3τ 2 ） 1/2 ≥σ S ; σ is dynamic compressive normal stress between the cladding and the base layer, the unit is pascal, σ and the longitudinal component speed V p of the cladding, which is perpendicular to the base layer, are in a proportional relationship with each other, V p cos (θ/2), τ is shear stress between the cladding and the base layer, the unit is pascal, τ and the transverse component speed V p of the cladding, which is parallel to the base layer, are in a proportional relationship with each other, V p sin (θ/2), wherein θ is the collision angle, (σ 2 +3τ 2 ） 1/2 is dynamic compressive equivalent stress, the unit is pascal, and σ S is greater dynamic yield strength in the cladding and the base layer, and the unit is pascal; In the step 4, the formula of conservation of function is P C-J k 0 SA/cos（θ/2）=1/2MV p 2 , wherein P C-J is the pressure on the detonation wave wavefront C-J of the explosive, the unit is Pascal, k 0 is a pressure adjustment coefficient, the value is 0.6-0.7, S is the area of a coating, the unit is square meter, A is the distance between the base layer and the coating, the unit is meter, θ is the collision angle, the unit is degree, M is the coating quality, the unit is kg, and V p is the impact speed of the coating, and the unit is meter per second.
  2. 2. The method according to claim 1, wherein in the step 1, a plate or a round tube having a smaller mass per unit area is selected as the clad layer in the explosion welding, a plate or a round tube having a larger mass per unit area is selected as the base layer in the explosion welding, and when the mass per unit area of the plate or the round tube is equal, either one of them is selected as the clad layer or the base layer in the explosion welding.
  3. 3. The method according to claim 1, wherein in the step 2, the minimum value V cmin of the collision point velocity V c satisfies: V cmin =（2R e （HV f +HV b ）/（ρ f +ρ b ）） 1/2 Wherein R e is Reynolds number, the value is 10.6, HV f is the Vickers hardness of the coating in pascals, HV b is the Vickers hardness of the base layer in pascals, rho f is the density of the coating in kilograms per cubic meter, rho b is the density of the base layer in kilograms per cubic meter; the maximum value V cmax of the collision point velocity V c is the minimum value of the cladding sound velocity and the base sound velocity in meters per second.
  4. 4. The method according to claim 1, characterized in that, according to the stress failure criterion of the fourth strength theory, the dynamic compressive equivalent stress (σ 2 +3τ 2 ） 1/2 reaches or exceeds the larger dynamic yield strength σ S in the cladding and the base layer when V p （2-cosθ） 1/2 ≥V pmin （2-cosθ min ） 1/2 ; Wherein V p is the coating impact speed, V pmin is the minimum value of the coating impact speed V p in meters per second, θ is the impingement angle, and θ min is the minimum impingement angle in degrees.
  5. 5. The method of claim 4, wherein the highest value of the dynamic compressive equivalent stress is 2-4 times the dynamic yield strength σ S corresponding to the lower welding energy limit.
  6. 6. The method of claim 1, wherein in step 5, the formula of conservation of momentum is ζ S ρ 0 V d =MV p , wherein ζ is the thickness of the charge in meters, S is the coating area in square meters, ρ 0 is the explosive density in kilograms per cubic meter, V d is the explosive detonation velocity in meters per second, M is the coating mass in kilograms, V p is the coating impact velocity in meters per second, and r is the ratio of the momentum of the explosive in the coating direction to the total momentum of the explosive.
  7. 7. The method of claim 6, wherein the Wherein gamma is the adiabatic index of the explosive explosion product, zeta is the thickness of the explosive, the unit is meter, N is the length of the coating, and N is more than or equal to 2.25 zeta.

Description

Design method of explosion welding process parameters Technical Field The invention belongs to the technical field of explosion welding, and particularly relates to a design method of explosion welding process parameters. Background The explosion welding is a processing technology for welding two metal plates together by utilizing the energy impact of explosive explosion, the explosion welding technology belongs to a solid state welding technology, a welding line is generated by high-speed impact of workpieces, the temperature of any workpiece can not be obviously increased, the substrate is not melted on a large scale, residual stress and brittle intermetallic compounds are seriously generated by adopting fusion welding in combination of dissimilar metals, and therefore, the fusion welding is not suitable for welding among dissimilar metals. Accordingly, explosion welding can weld not only the same kind of metal but also dissimilar metals with unique advantages that fusion welding does not have. Based on the current research conditions of explosion welding, the design of the process parameters of the explosion welding is still in a fumbling stage, and most of the process parameters are in an empirical formula, so that uncertainty exists in the welding effect, such as instability of the welding effect along with the change of the variety and/or size of welding materials, explosives and the like. Disclosure of Invention In view of the current research situation of explosion welding, the invention provides a design method of explosion welding process parameters, so as to solve the technical problem of reasonably determining the base coating interval and the medicine distribution thickness in the explosion welding process, and provide a new thought for the technicians in the field. The aim of the invention is mainly realized by the following technical scheme: the invention provides a design method of explosion welding process parameters, which comprises the following steps: Step 1, determining a base layer and a coating layer in explosion welding according to the unit area quality of welding materials, and arranging the base layer and the coating layer in parallel; step 2, determining the optional range of the collision point speed V c during explosion welding according to the material parameters of the base layer and the coating layer; Step 3, determining welding energy required by welding according to material parameters of a base layer and a coating, taking kinetic energy of the coating as a welding energy source, determining a minimum value V pmin of a coating impact speed V p during explosion welding according to minimum welding energy requirements, determining a value range of an impact angle theta by referring to a fourth intensity theory and welding energy requirements, and further determining specific values of the impact angle theta, the impact point speed V c and the coating impact speed V p; Step 4, determining a distance A between the base layer and the coating based on functional conservation according to the coating impact speed V p, the collision angle theta, the explosive explosion speed V d and the physical parameters of the coating and the explosive; and 5, determining the drug distribution thickness zeta based on conservation of momentum according to the coating impact speed V p and the explosive explosion speed V d as well as the physical parameters of the coating and the explosive. Further, in step 1, a flat plate or a round tube with smaller unit area mass is selected as a coating layer in explosion welding, a flat plate or a round tube with larger unit area mass is selected as a base layer in explosion welding, and when the unit area mass of the flat plate or the round tube is equal, either one of the flat plate or the round tube is selected as the coating layer or the base layer in explosion welding. Further, in step 2, the minimum value V cmin of the collision point velocity V c satisfies: Vcmin＝(2Re(HVf+HVb)/(ρf+ρb))1/2 Wherein R e is Reynolds number, the value is 10.6, HV f is the Vickers hardness of the coating, the unit is Pascal, HV b is the Vickers hardness of the base layer, the unit is Pascal, rho f is the density of the coating, the unit is kilogram per cubic meter, and rho b is the density of the base layer, the unit is kilogram per cubic meter; The maximum value V cmax of the collision point velocity V c is the minimum value of the coating sound velocity and the base sound velocity in meters per second. Further, in step 3, the welding energy and the kinetic energy of the coating are in a direct proportion relation, and the minimum value V pmin of the impact speed V p of the coating and the lower limit of the welding energy satisfy: 1/2MVpmin2η＝Ewmin＝σbSHfβδ Wherein M is the mass of the coating, S is the area of the coating, rho f is the density of the coating, the density is kilogram per cubic meter, H f is the thickness of the coating, the density is meter, 1/2MV pmin2 is