Made by Bo Zhou，Email: zhoubo@
11
Mechanics of Composite Materials
3. Particulate Composites Particulate composites consist of particles of one or more materials suspended in a matrix of another material. The particles can be either metallic or nonmetallic as can the matrix. Nonmetallic in nonmetallic composites Metallic in nonmetallic composites Metallic in metallic composites Nonmetallic in metallic composites
Made by Bo Zhou，Email: zhoubo@
12
Mechanics of Composite Materials
1.3 Mechanical Behavior of Composite Materials
1. Homogeneous and isotropic A homogeneous body has uniform properties throughout, i.e., the properties are not a function of position in the body.
Made by Bo Zhou，Email: zhoubo@
2
Mechanics of Composite Materials
1.1 Introduction 引言
1. Composite Materials
The word “composite” in composite material signifies that two or more materials are combined on a macroscopic scale to form a
useful material.
复合材料 复合材料中的“复合”这个词表示由两种或多种 材料ቤተ መጻሕፍቲ ባይዱ宏观尺度上组成的一种有用的材料。
Made by Bo Zhou，Email: zhoubo@
3
Mechanics of Composite Materials
复合材料的优点是，具有各种组分的最好特性，并且有 些特性是组分材料所没有的，复合材料能改善的特性有 • • • • • • • • • • • Strength –强度 Stiffness – 刚度 Corrosion resistance – 耐腐蚀性 Wear resistance – 耐磨性 Attractiveness – 吸引性 Weight – 重量 Fatigue life – 疲劳寿命 Temperature-dependent behavior – 与温度有关的性能 Thermal insulation – 绝热性 Thermal conductivity – 导热性 Acoustical insulation – 隔音性
6
Mechanics of Composite Materials
Dodge Viper
Front grill of an Automobile
Different part of an airplane
Made by Bo Zhou，Email: zhoubo@
7
Mechanics of Composite Materials
Made by Bo Zhou，Email: zhoubo@
5
Mechanics of Composite Materials
Composite Bicycle Laminated Fiberglass Bow
Graphite Snowboard
Made by Bo Zhou，Email: zhoubo@
1 Introduction to Composite Materials 第1 章 复合材料介绍
1.1 Introduction 引言[Enter] 1.2 Classification and Characteristics of Composite Materials 复合材料的分类与特性[Enter] 1.3 Mechanical Behavior of Composite Materials 复合材料的力学性能 [Enter] 1.4 Basic Terminology of Laminated Fiber-reinforced Composite Materials 层合纤维复合材料的基本术语[Enter]
Made by Bo Zhou，Email: zhoubo@
9
Mechanics of Composite Materials
2. Laminated Composites Laminated composites consist of layers of at least two different materials that are bonded together. Lamination is used to combine the best aspects of the constituent layers in order to achieve a more useful material. Bimetals Bimetals are laminates of two different metals with significantly coefficients of thermal expansion. Clad metals The cladding or sheating of one metal with another is done to obtain the best properties of both.
Made by Bo Zhou，Email: zhoubo@
8
•
Mechanics of Composite Materials
1. Fibrous Composites Long fibers in various forms (fiber and whisker) are inherently much stiffer and stronger than the same material in bulk form. Properties of fibers A fiber is characterized geometrically not only by its high length-todiameter ratio but by its near crystal-sized diameter. Properties of whiskers A whisker has essentially the same near crystal-sized diameter as a fiber, but generally very short and stubby although the length-todiameter ratio can be in the hundreds.
1.2 Classification and Characterisitcs of Composite Materials 复合材料 的分类与特性
There are three commonly accepted types of composite materials: • • Fibrous composites which consist of fibers in a matrix 纤维复合材料，由纤维和基体组成 Laminated composites which consist of layers of various materials 层合复合材料，由多种材料层合组成 Particulate composites which are composed of particles in a matrix 颗粒复合材料，由颗粒和基体组成
Mechanics of Composite Materials
复合材料力学
Mechanics of Composite Materials
教材：R. M. 琼斯：复合材料力学（英文）
Made by Bo Zhou，Email: zhoubo@
1
Mechanics of Composite Materials
Made by Bo Zhou，Email: zhoubo@
4
Mechanics of Composite Materials
2. Usages of Composites 复合材料的应用
自古以来，人们就会使用天然的复合材料——木材、竹、骨骼等。
最原始的人造复合材料是在粘土泥浆中掺稻草，制成土砖；在灰泥
Made by Bo Zhou，Email: zhoubo@
10
Mechanics of Composite Materials
Laminated glass Window glass is durable enough to retain its transparency under the extremes of weather. However it is quiet brittle and is dangerous because it can break into many sharp-edged pieces. On the other hand, a plastic called polyvinyl butryal is very tough (deforms to high strains without fractue), but is very flexible and susceptible to scratching. Safety glass is a layer of polyvinyl butyral sandwiched between two layers of glass. The glass in the composite protects the plastic from scratching and gives it stiffness. The plastic provides the toughness of the composite. Thus, together, the glass and plastic protect each other In different ways and lead to a composite with properties that are vastly improved over those of its constituents.