Axial Compression Test of Hat-Shaped Specimens

Introduction

In the automotive industry, improvement of automobile fuel economy as a countermeasure for global warming has become a critical issue in recent years. Although various measures such as reducing the air resistance of the auto body and reducing the rolling resistance of the tires are conceivable, one of the most effective measures is reduction of auto body weight. Reducing the thickness of members can be considered as an approach for reducing auto body weight, but on the other hand, safety requirements must also be satisfied. High-strength materials are being developed from this viewpoint. As examples, CFRP (carbon fiber reinforced plastic) and high tensile strength steel may be mentioned. CFRP is a resin material which is reinforced with carbon fiber, and has particularly high specific strength and specific rigidity, even among composite materials. CFRP in which thermosetting resin is used as the matrix resin is already used in racecars and luxury vehicles, and in recent years, CFRTP (carbon fiber reinforced thermoplastic composite) has also been developed by using a high formability thermoplastic resin as the matrix resin. On the other hand, high tensile strength steel is a class of materials with higher strength than general structural steel, and materials with strength of 1,000 MPa or more have also been developed. In this research, hat-shaped specimens of CFRTP and high tensile strength steel were prepared as hollow frames, which are used in large numbers in automobile bodies, and were subjected to an axial compression test. In addition to measuring the compressive strength of the respective materials, video recording synchronized to the test results was also performed in order to identify the fracture point.

June 6, 2019 GMT