*Article* **Metallic Glasses: A New Approach to the Understanding of the Defect Structure and Physical Properties**

**Vitaly Khonik 1,\*,† and Nikolai Kobelev 2,†**


Received: 25 April 2019; Accepted: 20 May 2019; Published: 24 May 2019

**Abstract:** The work is devoted to a brief overview of the Interstitialcy Theory (IT) as applied to different relaxation phenomena occurring in metallic glasses upon structural relaxation and crystallization. The basic hypotheses of the IT and their experimental verification are shortly considered. The main focus is given on the interpretation of recent experiments on the heat effects, volume changes and their link with the shear modulus relaxation. The issues related to the development of the IT and its relationship with other models on defects in metallic glasses are discussed.

**Keywords:** metallic glasses; defects; structural relaxation; heat effects; shear elasticity; interstitialcy theory
