Study on micro/nano-indentation of typical soft-brittle materials

As a typical multi-functional single crystal material, Lithium tantalite (LiTaO3 or LT) exhibits its excellent electro-optical, piezoelectric properties and has now been widely applied into many applications, such as surface acoustic wave (SAW) filters, isolators and other photoelectron devices. Compared with other functional crystals like silicon and sapphire, LT behaves much more brittle and softer. The knowledge of precision machining built on conventional hard-and-brittle materials is no longer applicable to this new type of soft-and-brittle crystal. In order to clarify the fundamental mechanical properties of LT, micro/nano-indentation tests are conducted in this study. The obtained results are analyzed and discussed to understand the behavior of this type of materials in their machining process.