Access Type

Open Access Thesis

Date of Award

January 2012

Degree Type


Degree Name



Mechanical Engineering

First Advisor

Emmanuel Ayorinde


Acrylonitrile-Butadiene-Styrene (ABS) represents a family of engineering thermoplastics with a wide field of performance characteristics. ABS materials have been receiving a great deal of attention because of their unique properties, such as outstanding formability, high tensile strength and stiffness, very high impact strength, excellent ductility, excellent high and low temperature performance, and resistant to many chemicals and plasticizers. Particularly, ABS exhibits really high impact strength; therefore, it is used in industry products which require high impact strength materials, such as military helmets and construction safety helmets. The vibration analyses of ABS rectangular plates are incredibly significant for design in military applications. The modal parameters of three various ABS rectangular samples, such as deflection mode shapes, resonance frequencies and damping ratios, were obtained in the frequency range of 0 Hz to 6400 Hz by the PULSE 15.1 software which is produced by the Bruel&Kjaer company. The Lancsoz Eigensolver method in ABAQUS/STANDARD 3D software, which is a powerful tool for extraction of the extreme Eigenvalues, was used to determine the natural frequencies and mode shapes of the ABS rectangular samples. The modal densities of the samples were experimentally determined in the frequency range of 0 Hz to 12800Hz to find out which sample requires a more effort and money in design process. The experimental and finite element results were compared very favorably with one another.