Japanese
   〒464-8603
Fro-cho, Chikusa-ku, Nagoya
 
 
  
 
Research Topics in Arai Lab. 
  
 
Characterization of carbon fiber-reinforced plastic (CFRP)   
   
Carbon fiber-reinforced plastics (CFRPs) are used as a structural material in major airplanes, e.g., Boeing 787 and Airbus A380, because of its high specific strength and stiffness. In recent years, CFRPs have been applied to primary structures such as wings, leading to weight reduction and high fuel efficiency of airplanes. Our research group performs experiments (e.g., a strength test, a fracture toughness test, and fatigue crack growth test) to evaluate the mechanical properties of CFRP laminates. We also carry out numerical simulations using a finite element method (FEM) or a boundary element method (BEM).
   
Development of carbon nanotube reinforced composites 

Nowadays, carbon nanofibers (CNFs) and carbon nanotubes (CNTs) are attracting attention because of their features. Our research group investigates the mechanical properties (e.g., elastic moduli and a tensile strength) and the physical properties (e.g., an electric conductivity and a thermal conductivity) of polymer matrix composites using CNFs or CNTs as reinforcing fillers. Through these studies, we aim to develop high-strength and high-functional composite materials and examine their use as structural materials in automobiles, airplanes, etc. In particular, we focus on the study of carbon fiber-reinforced plastic (CFRP) laminates reinforced by CNTs or CNFs.

 
 
 
   
Material evaluation by resonant ultrasonic spectroscopy (RUS)   
 
 

Resonant ultrasonic spectroscopy (RUS) is a method for determining the elastic and viscoelastic moduli of solid materials by measuring resonance frequencies. In this laboratory, an experimental system using a piezoelectric element is used to excite vibration. Then, an inverse analysis method using a boundary element method (BEM) or a finite element method (FEM) combined with a genetic algorithm (GA) is applied. We examine the technique to evaluate the elastic and viscoelastic moduli (parameters of elasticity and viscosity) of the anisotropic materials with high accuracy.

   
Evaluation of material physical property by using laser ultrasonic waves    

Much attention has been paid to the testing technique using laser ultrasonic waves to measure the physical properties of the material. In this method, the irradiated laser pulse generates an elastic ultrasonic wave inside the solid materials, and the material strength is estimated by using reflections and interferences of the wave. Our research group investigates the method for measuring the interfacial adhesion strength and fracture toughness of coating films using laser ultrasonic waves.

 
 
   
Numerical simulation for press forming of glass lenses 
 

The high-temperature press forming method of glass lenses for electronic devices has been attracting attention with an increase in the demand for aspheric lenses. In this laboratory, the thermal viscoelastic property of glass lenses is evaluated by a creep test. A press forming process is also simulated by using the general-purpose finite element method (FEM) code. The main targets of this study are lenses for digital cameras, on-board cameras, liquid crystal projectors, etc.