材料导论第一章课后习题参考答案

本答案版权归北京化工大学朱文墨所有1-1：(a) Engineering materials is a term often loosely used to define most materials that go into products and systems.(b) Engineering materials technology covers fields of applied science related to materials, materials processing, and the many engineering specialties dealing with materials, such as research and development, design, manufacturing, construction, and maintenance.(c) Materials are the matter of the universe.(d) Materials science. The “science” focus on discovering the na ture of materials, which in turn leads to theories or descriptions that explain how structure relates to composition, properties, and behavior.(e) The materials engineering “deals with the synthesis and use of knowledge [structure, properties, processing, and behavior] in order to develop, prepare, modify, and apply materials to specific needs.(f) Materials science and engineering. As defined by a National Academy of sciences study, MSE involves the generation and application of knowledge relating the composition, structure, and processing of materials to their properties and uses.(g) The term properties describes the behavior of materials when subjected to some external force of condition.1-2: Steel, wood and stone.1-3: Engineering plastics are those plastics and polymeric compositions for which well-defined properties are available such that engineering rather than empirical [trial and error [methods can be used for the design and manufacture of products that require definite and predictable performance in structure applications over a substantial temperature range.Polycarbonates and acetals.General-purpose plastics do not possess the properties to carry heavy loads bur serve as packaging, upholstery, and so on.Polystyrene and vinyl.1-4: (a) Synthesis involves transforming the atoms and molecules of gases, liquids, and solid elements by chemical and physical means to form other, solid materials.(b) Although it also deals with atoms and molecules, materials processing “includes co ntrol of structure at higher levels of aggregation and may sometimes have an engineering aspect”.(c) Bulk materials are the products of synthesis, materials extraction, refinement, and processing.(d) Components include fears, electrical wires, screws, nuts, jet engine turbine blades, brackets, levers, and the thousands of constituent parts that go into many products and systems.(e) Devices, which include microprocessors, resistors, switches, and heating elements, are usually more complex than components and are designed to serve a specific purpose.(f) Products are individual units, such as roller-blade skates, television sets, chairs, and telephones.(e) Systems are an aggregate of products, components, and devices.1-5: Actually they are one thing. The new-generation engineering materials are often designed materials; they have been engineered to provide designated properties. In other words, instead of selecting from a list of available materials, designers may specify the desired properties for their needs and then rely on materials engineers and technologists to create materials to suit the need.1-6: The life cycle analysis of products can determine their impact on the global environment. LCA looks at all the factors involved in a product by making an inventory of the inputs and outputs.A life cycle inventory is a listing of raw materials, bulk materials, gas emissions, product waste, recyclables, and so on.The aim of LCA is to determine their impact on the global environment.1-7: Extracting raw materials;Creating bulk materials, components, and devices;Manufacturing engineered materials;Fabricating products and systems;Service of products and systems;Recycling/disposing of used products and systems.1-8: Smart materials are materials designed to mimic biological organisms.Nitinol, electrorheological and magnetorheological fluids, and piezoelectric materials.1-9: It is a new method developed to produce materials that blend synthesis with processing by beginning with one of the chemical agents already in the form of its final shape.1-10: Mimic is to look or behave like something else. So biomimicking is to look or behave like other living tissues.Biologically inspired materials are materials that have the ability to: (1) self-assemble, (2) self-heal, (3) morph or change shape in response to stress, (4) change color, etc.1-11: The studies of engineering mechanics (study of forces in a materials system), durability, and engineering design.1-12: Designing for disassembly places recycling at the beginning of design stage of the materials cycle in order to facilitate recycling. Designing for assembly consider repair issues early in the design stage and make repairs less costly. When a machine or a set is much easier to assemble, customers may fix it rather than tossing them out if it is broken.1-14: If a product is designed for disassembly, this product can be broken into components for easy soring prior to recycling when its life is over. Today, LCA has caught much more attention than before, the most important phase between the beginning and the end of the LCA is recycling. If this step is well carried out, then the whole cycle will become reality.1-15: Sustainable environmental technologies are practices that ensure we do not pollute and we make the best use of our natural resources. Green manufacturing, a major global effort, seeks to make all phases of the materials cycle environmentally friendly, thereby placing the least amount of stress on the delicate balance of nature.1-16: The systems approach places the materials engineers and technologists together with the design engineers, technicians, manufacturing engineers, plus the environmental engineers and even marketing personnel. Using this method can ensure that appropriate safeguards are implemented to protect the environment as well as present and future human generations.1-17: Placing recycling at the beginning or design stage of the materials cycle can ensure that waste going into municipal landfills will be minimized.1-18: Yes, it is a matter of cost and material properties. But there are some other factors should be considered, such as availability, processability, quality, performance, consumer acceptance.1-19: To ensure that waste going into municipal landfills will be minimized.1-20: They consume huge quantity of resources and are not degradable.1-21: Metallics, polymerics, ceramics, composites and others.1-22: Metals: A type of solid mineral substance that is usually hard and shiny and that heat and electricity can travel through, for example tin, iron and lead.Alloys: A metal that is formed by mixing two types of metal together, of by mixing metal with another substance.Powdered metals:1-23: Ferrous, nonferrous, powdered metal metallic nanotubes.1-24: Ferrous: Iron, steel, cast iron.Nonferrous: Aluminum, tin, zinc, magnesium, copper, gold, gold.1-25: Producing small particles, compacting, sintering.1-26: There are several reasons for not using pure metals----they may be too hard or too soft, or they may be too costly because of their scarcity----but the key factor normally is that the desired property sought in engineering requires a blending of metals and elements.1-27: Polymer: A natural or artificial substance consisting of large molecules that are made from combinations of small simple molecules.Polymeric: Something that is related to polymer.Monomer: A molecule that can be bonded to other identical molecules to form a polymer. 1-28: Polymerization: The act of combining, or making units of a chemical combine, making a polymer.1-29: Plastic means easily formed into different shapes.1-30: Thermosets: Vulcanized rubber, epoxies, polyester resin.Thermoplastics: Polyethylene, polypropylene, polycarbonate, polystyrene.1-31: 猜测TPs是thermoplastics,可是thermosetting plastics的缩写难道是TSPs？傻傻分不清。