Wedge Peel Impact Test on Adhesives

ISO 11343 is a standardized Wedge Peel Impact test method used to measure the resistance of high-strength structural adhesives. 

Why Wedge Peel impact testing on adhesives is important 

The use of high-strength structural adhesives in industry is increasingly growing as manufacturers have become aware of their advantages over conventional joining techniques. Providing high-performance adherent to aluminum, steel and other materials, adhesives bond materials are transversal to many different industries: from automotive to aerospace, electronics, medical, sports and construction. These new bonding materials are rapidly replacing mechanical fasteners to join structural frame assemblies, body panels and hem-flanges, metals, composites, rubber, glass, windshields, and other components. They help improve durability, reduce weight, and reduce manufacturing costs.

In the automotive industry, reliability and durability are the most important characteristics, and structural adhesives meet these criteria better than almost all others. Increased use of these adhesives in the automotive industry, especially in safety-critical areas, makes it necessary to ensure the high performances and structural integrity of the bonds under real life conditions. For instance, impact forces in a crash test may cause failure in bonded areas resulting in serious injury to vehicle passenger.

car and glue

How to perform a wedge-peel impact test

A wide range and variety of test methods are available to determine suitability of various adhesives to adhere different substrates for long use in the field. Test methods consider various types of stress such as tension, compression, and peel. In addition, the environmental conditions which the adhesive bond will encounter in its service life play an important role to predict the potential life of the bond. ISO 11343 is a standardized Wedge Peel Impact test method used to measure the resistance of high-strength structural adhesives to cleavage fracture at various speeds and user-defined temperatures.

impact wedge peel specimens

The impact test consists of a wedge with a defined shape and mass, being driven at a defined velocity into the adhesive bond securing two metallic surfaces causing the bond to fracture and the adherends to peel apart. The test provides the data necessary to calculate the dynamic resistance to cleavage, which is defined as the force per unit of width necessary to bring an adhesive joint to failure. This vital information can be used to aid manufacturers in the research and development of new adhesives. When a suitable product has been established, both manufacturer and end-user can implement a quality control program utilizing baseline data from the impact performance tests to provide ongoing process validation and quality control.

adhesive specimen

When performing impact wedge peel tests, the Instron 9450 Drop Tower can be equipped with thermostatic chamber and accessories dedicated to ISO 11343. These include a vice with a high-performance Strain Gauge force sensor embedded, both symmetric and asymmetric wedges per ISO requirements and a dedicated striker.

impact wedge peel set up

The thermostatic chamber enables the user to test at low and high temperatures and experiment with different material compositions, cure conditions and climatic temperatures to optimize product performance and comply with government regulations. Real life testing scenarios can be simulated within the range from -40°C to +80°C, very typical climatic conditions for the automotive industry.

The high-resolution data acquisition chain, combined with Bluehill Impact Software have been developed to deliver accurate results and reduce the chances of human error.

With the combined use of a Drop Tower system equipped with Bluehill Impact Software, wedge-peel accessories, High Speed Camera it is possible to investigate the fracture behavior of the specimen when impacted.

high speed camera impact wedge peel test

Originally posted By Francesca Pinto On Oct 27, 2021 , Updated On January 16, 2023