© December 2018 | IJIRT | Volume 5 Issue 7 | ISSN: 2349-6002 IJIRT 147354 INTERNATIONAL JO URNAL OF INNOVATIVE RESEARCH IN TECHNOLOGY 203 Design and Development of 90 Degree Peel Test Setup Darshan Awale 1 , Shrushti Abhyankar 2 , Suruchi Gujarathi 3 , Gautami Keskar 4 1,2,3,4 Student, Mechanical Engineering Department, Maharashtra Institute of Technology, Pune Abstract- Delamination is failure in a laminated material, often a composite, which leads to separation of the layers of reinforcement or plies. Peel testing is one way to characterize adhesive bonds. It is used extensively to evaluate the bonding strength of tape, adhesives and flexible substrates. The peel test is used to determine the adhesion between soft (Adhesives & PVB) and hard (Glass, fiberboard, steel and liner material) materials. Peeling test is the practice of testing adhesion properties of film bonded to a substrate. The designed peel test setup uses Universal Testing Machine (UTM) as the measuring aid and the setup is assembled onto it. The setup ensures minimum friction during the sliding motion. The voluntary motion of the sliding plate eliminates the use of a motor or a separate mechanism to enable horizontal motion. The support block and buck mechanism serve their respective purposes for the test to be carried out. The setup is connected to a computer that has ‘Win UTM’ software to convert the experimental results into numerical data required for further analysis. Index Terms- Peel test, Crack Nucleation, Crack Propagation, Tensile modes of Delamination, Tribology. I. INTRODUCT ION Interfacial delamination is the separation of two materials across the interface. In laminated materials, repeated cyclic stresses, impact, vibration loadings, etc. can cause layers to separate with significant loss of mechanical toughness. Delamination also occurs as a result of corrosion. The adhesive strength of peel tests exist depending on the peel angle, namely 90° and 180° peel tests. The peel angle is the angle between the interface direction and the direction of the peel force (Refer Fig 1). Adhesives are used to bond separate materials or small parts together. They are widely used in our daily life, industrial manufacturing, and scientific research. Adhesion interaction takes the dominant role in the performance of adhesives. The adhesives diffuse into the holes of the substrate at the interface. After solidification or gelation, the substrate and adhesives interlocks. Some of the important factors influencing the adhesives include fatigue strength, impact strength, yield strength and durability. Fig 1: Geometry of 90 degree Peel Test II. LITERATURE REVIEW Crack Nucleation Crack nucleation occurs when the radial stress acting at the interface between a rigid cylindrical inclusion and the matrix reaches a critical value. The radial stress is computed by considering both the stress accumulated due to the residual stress associated with strain concentration around the inclusion and the stress due to the applied load. When the normal load is higher than four times the critical shear stress of the metal, the rate of crack propagation per loading cycle as well as the crack nucleation rate. The size of the region over which cracks nucleate also increases with increased applied loads. Crack Propagation