Using nano-scratch testing to detect composite failure Composite materials are more and more commonly used in a growing number and variety of applications. Material health testing, measurement and control needs are also increasing significantly, especially for structural parts. By testing - Using nano-scratch testing to detect composite failure ............................ p45 - Processing technology for the rapid production of advanced composites .. p49 Research & development JORGE RAMIREZ, APPLICATIONS SPECIALIST NANOVEA C omposite materials combine two constituent materials: a matrix and a reinforcement. The reinforcement enhances the properties of the matrix material. Combining various materials in different formulas makes it possible to create new materials and to control the resulting synergistic properties. Thus, the challenge is to create a formula where each ingredient interacts with one another to yield the intended results. Nano-scratch testing for quality control One of the major concerns for composite materials is the durability of the final material. The size of the particles that form the strengthening additive can drastically affect the overall final performance of the composite. The nanoscratch testing method can be used to compare the failure behaviour of various materials in order to identify the formula that results in the most durable composite. The scratching process has to be simulated in a controlled and monitored manner to observe its effects on sample behaviour. In this application, the Nanovea Mechanical Tester is used in its nano-scratch testing mode to measure the load required to cause the failure of several composite material samples. Two of the samples include a micro-size hard-phase additive; a third one includes a nano-size hard-phase additive. A 5 µm diamond tipped stylus is used to scratch the coating at a progressive load ranging from 0.06 mN to 120 mN. The point where the coating fails by cracking is taken as the point of failure. Three tests are carried out on each sample in order to determine the exact critical failure load. Fig. 1: Nanovea Nanoindenter No64 April 2011 / jec composites magazine 45http://www.jeccomposites.com/events/jec-show-americas-2012