An armored truck cab design : Case study: investigation of selected steel grades

Sammanfattning: This study aimed at defining useful guidelines for the design of an armored truck cab. Particularly, the quality and performance of ballistic steel were defined, considering not too high demanding requirements. Two steel grades, corresponding to hardness of 500 HB and 600 HB, and three different suppliers were selected. After dividing the truck cab into main areas, a FEM simulation was performed. The investigated model considered a specific standardized threat to impact against a double layer steel protection. Due to the high strain rates involved, the formation of adiabatic shear bands has been observed. However, the main purpose of the model was to find an ultimate thickness protection layout of armored steel plates. Thereby, the thicknesses to be attributed to the various components of the main areas could be estimated. Two alternatives were therefore hypothesized: the first considering the critical thickness case of penetration, and the second, an oversized version, supposed to be more resistant to penetration. It was thus possible to estimate the weight of the truck cab for the two above mentioned alternatives, and verify such hypothesized weight complied with the assigned requirement. A possible cutting operation was then considered in order to optimize the use of the steel plates. An estimation of the pre-series production costs of was finally derived.