873.60 Enamel fracture 873.61 Crown fracture without pulp involvement 873.62 Crown fracture with pulp involvement 873.63 Root fracture 873.64 Crown-root fracture 873.66 Tooth luxation (dislocation) 873.67 Intrusion or extrusion 873.68 Avulsion 873.69 Other injuries

1、基本概念 Concept 2、屈服强度 (Yield Strength) 3、断裂强度 (Fracture Strength)

The Fundamental problem The Fundamental problem Bones get less dense as we age Bones get less dense as we age Old people with low density bones Old people with low density bones fracture easily fracture easily Space -flight rapidly causes bones to flight rapidly causes bones to get less dense get less dense

1. Compare Stearns' Type 2 fracture pattern to the okljoints from the class notes. Draw a diagram and discuss the nature and occurrence of the fracture(s)

7.1 Basic physical quantities 7.2 Mechanics properties of rubber elasticity Griffith Theory 7.3 Fracture Mechanics of Brittle Materials Stress, strain, modulus Theory of rubber elasticity 7.4 Fracture properties of polymer in glassy and crystalline state

The role of Mg in alloy/718 has been systematically investigated. Mg raises not only high temperature tensile and stress-rupture ductilities but also increases considerably smooth and notch stress-rupture life. Mg containing alloy 718M is free of stress-rupture notch sensitivity. Mg improves creep and fatigue interaction properties （LCF or cyclic stress rupture） at any grain size. The basic role of Mg is equilibrium segregation at grain boundaries which helps to change continuous grain beundary (5-Ni3Nb morphology to discrete globular form which has a retardation effect on intergranular fracture. Mg promotes the change from intergranular to transgranular fracture mode

The relationspip between the microcracks and the mechanical behaviors and the characteristics of fracture of MDF cement have been studied. The results show that most of the microcracks lie and propagate in the matrix or along the boundary of the clinkers. The microcracks improve the toughness of MDF cement. The Griffith’s equation is invalid to describe the fracture of MDF cement

⚫ Discuss macroscopic and microscopic aspects of the mechanical behaviors of metallic materials; ⚫ Concern with metallurgical principles including crystal structure, materials science and fracture mechanics---- mechanical metallurgy; ⚫ The crystal physics approach: the role of dislocations in controlling mechanical properties; ⚫ The classical metallurgical approach: the relationship between microstructure and properties; ⚫ The fracture mechanics approach: the relationship between material toughness, design stress, and allowable flaw size

《材料失效分析 Materials Failure Analysis》课程教学资源（参考书籍）Fracture Appearance and Mechanisms of Deformation and Fracture

《材料失效分析 Materials Failure Analysis》课程教学资源（参考书籍）Fracture of Brittle Solids——Fracture of Brittle Solids（Second Edition）