DOE approach in the FE Simulation of Liner Forging Process

실험계획법을 적용한 라이너 단조 공정의 유한요소해석

Abstract

A liner is a crucial component that directly affects the penetration performance of the shaped charge warhead. If the material of the liner has fine grain size and high strength, then the penetration performance can be further improved. There have been attempts to use a preform obtained by a severe plastic deformation (SPD) process. In this study, the process of minimizing the strain deviation to maintain the characteristics of material obtained by the severe plastic deformation process was investigated. The FE analysis of liner forging process was performed using the design of experiments (DOE), to optimize various shape parameters of the forming process such as shape of preform and forging die. As a result, the combination of design variables with the minimum effective strain deviation in the liner forging process were obtained.

Fig. 1 The mechanism of jet generation on shaped

Fig. 2 The forming sequence of liner

Fig. 3 The schematic diagram of numerical DOE analysis system

Fig. 4 Design variable definition of preform and forging die

Fig. 5 Preform after preliminary forging and cutting

Fig. 6 Variation of shape and effective strain with punch stroke in liner forging process(Case2)

Fig. 7 Comparison of effective strain according to shape of preform at specific cross-section

Fig. 8 Plot of main effect of die diameter(C) according to shape of preform

Fig. 9 Plot of main effect of die angle(D) according to shape of preform

Fig. 10 Plot of main effect of punch angle(E) according to shape of preform

Fig. 11 The chart of rank correlation for design variables

Fig. 12 The effective strain deviation predicted from each samples

Table 1 Definition of design variables and level

Table 2 Orthogonal array table of design variables

Table 3 Minimum value of effective strain deviation