Under the lead of Dr. Johnny Zhou, the research team of Protech made a great progress in the field of the ballistic response mechanism of UHMWPE composite materials collaborating with the Composite Materials Research Institute of Tiangong University . And some academic papers have been published on SCI and EI journals.

The latest research achievement of Protech research team with the title of “ Influence of projectile physical state on ballistic energy absorption capacity of UHMWPE laminate Experiment and Simulation” was launched on the authoritative journal “Composite Structure”( Top Journal in the field of composite materials, Impact Factor 6.3) on October 11, 2023.

Paper link:https://doi.org/10.1016/j.compstruct.2023.117607

This paper discussed the influence of projectile physical state on ballistic energy absorption capacity of UHMWPE laminate and showed the simulation results of velocity evolution of projectile during ballistic impact and performed decoupling parametric studies of projectile state.

 Fig. 1 X-ray cross-section damage morphologies of post-impact UHMWPE composite laminate at impact point: (a) Laminate perforated by 17 gr FSP; (b) Laminate perforated by MSC.

From the Fig. 1, it can be seen that cross-section morphologies of post-impact laminate perforated by FSP and MSC have similar damage mode, and all can be divided into two parts (Part I and Part II). The part I was the local perforation response and the sub-laminate in this part was mainly destroyed by shear. Then, the part II was the local/structural coupled response. The noticeable damage of sub-laminate in part II was out-of-plane bending deformation. In addition, the sub-laminate also features the coupling fracture of shear, tensile deformationand melting.

 According to perforation ballistic damage morphologies and combined with empirical curves of the evolution of projectilevelocity, the progressive perforation ballistic damage process may be divided into three stages (A, B, and C), as shown in Fig. 2a, which was verified by finite element simulation, as shown in Fig. 2b. Duringperforation process, the projectile was mainly subjected to a deceleration response process, whose deceleration gradually decreases. Moreover, the laminate will undergo first a short acceleration response process followed by a deceleration response process. 

Fig. 2 Empirical curves of velocity evolution of projectile and sub-laminate during perforation ballistic impact process, and finite element simulation verification

 Fig. 3 Cross-sectional views evolution of numerical laminate at impact point

(The influence of projectile physical state on bulletproof performance of UHMWPE composite laminate through finite element simulation in a decoupling manner)

Then, according to the verified digital model, decoupling parametric studies of projectile physical state were carried to investigate the effect of spin velocity, deformation, caliber, and mass on bulletproof performance of UHMWPE composite laminate, as illustrated in Fig. 3. The results indicated that the projectile spin mainly reduced bulletproof performance by causing torsional deformation of laminatewhile the deformation, caliberand mass of the projectile all affected bulletproof performance by affecting the ballistic response area of the laminate.

Except these the research achievement of Protech research team with the title of “ Ballistic response of ultra-high molecular weight polyethylene laminated impacted by mild steel core projectiles” was launched on the international journal of Impact Engineering （Top journal in The field of Impact. Impact fact 5.1) on 29th July, 2022.

This paper presented the effect of interlaminar shear strength on ballistic performance of UHMWPE composite laminateand discussed the detailed progressive ballistic damage process and internal damage morphologies. Based on damage patterns, an evaluation model of laminate energy absorption was established to analyze the dissipation mechanism of the kinetic energy of the projectile.

Paper link : https://doi.org/10.1016/j.ijimpeng.2022.104338