Selecting an engineering material is like choosing a dress for a particular occasion. What works for a retro party would surely not work for a formal dinner.
Depending upon the type of equipment or machine, we use different types of materials. We need to pay so much attention to material selection because it is one of the foremost functions of effective engineering design. It determines the reliability of the design in terms of industrial and economical aspects.
For example, a machine that has to be used underwater would require a material that can long endure corrosion effects. Various factors like working conditions, environmental exposure, and operational temperature have a huge impact on the life and efficiency of a machine or equipment, and if materials are not chosen considering these factors at the time of manufacturing, it might have serious implications.
The following is a carefully chosen collection of articles that will help you gain new knowledge (or refresh yourself) about engineering materials and processes.
Even in the primitive age human beings were civilized and knew how to use different materials in their construction and simple tools. Today we apply terms like Stone Age, Bronze Age, and Iron Age to indicate how competent early man was in dealing with different types of materials. Even the modern science of metallurgy originally evolved from primitive methods of mining.
Material selection can make the difference in whether a great design can lead to a profitable product. Other factors to be considered are the mechanical properties of a material, its resistance to corrosion, and cost effectiveness.
Material testing is an important aspect of material engineering and manufacturing processes. Unless a material is tested for stress, strain, ductility, permeability, and other factors, it cannot be deemed fit for use. This article provides detailed information about the various types of tests and testing equipment, as well as how to assess the mechanical properties to confirm a material's suitability for the fabrication of a component.
Ultimate tensile strength, ductility, necking, fracture, impact strength, and metal fatigue are some of the mechanical properties involved in material selection. These properties are related to each other and help in designing efficient and long lasting mechanical equipment.
Taps and dies are thread cutting tools that perform the basic function of forming solid connections between different parts of a machine. Taps are used for making internal threads whereas dies are used for making external threads.
Innovations have helped the manufacturing industry make use of non-conventional materials in the manufacturing processes. One of the earliest successes was working with plastics that can be formed with heat and retain their shape when cooled. Today a number of processes, including injection molding and extrusion, are used with thermoplastics.
Nanotechnology has evolved as a science dealing with materials at microscopic levels. Nanotechnology entails the application of fields of science as diverse as semiconductor physics, organic chemistry, and microfabrication. Nanotechnology based tools are of great use in heavy industry, aerospace industry, and the construction sector.
Different materials have different acid-base properties and react differently to different environmental factors like air and water. Most definitions of organic compounds have traditionally been based on the concept of their having some relation to living mater. Modern synthetic organic compounds, however, suggest that we may need an updated description.
Mechanical loading often results in stress, and sometimes the stress acts at unusual angles. Material testing is done in the laboratory, where we can never replicate real-time conditions, so investigation of metal failures that have actually happened helps in overcoming the shortcomings in future designs. It also helps in understanding loading patterns under different conditions that are hard to simulate.
One of the best ways to protect your engineering material from external factors like corrosion and fatigue is through thermochemical treatment. Nitriding is one such process. It covers the exposed surface of the working metal with nitrites of iron, chromium, molybdenum, nickel, and thereby offers greater hardness.
Carburizing is another method used to harden metallic surfaces. Hard steel tends to be brittle, but with the help of carburizing we can ensure that the steel does not give way under extreme wear conditions.
Tungsten gas arc welding is also called Tungsten Inert Gas welding (TIG) and is a spatter-free precision welding method. We can weld joints, butts, edges, and corners with this method with only minor distortion of the work piece. TIG welding is practically smoke free and can be used to weld at different angles, which is not possible with conventional methods.
Scientific studies prove that nanotubes have hundreds of times better tensile strength compared to steel, thermal conductivity better than all but the purest diamond, and electrical conductivity almost similar to copper. Nanotubes also have wonderful electronic, optical, and chemical properties. A specific class of self-replicating nanotubes is expected to effectively revolutionize the expense and ease of manufacturing certain fabrics and thin sheets. However, there is also the problem of the unfounded and ridiculous public perception that the self-replicating process could "go wild."
Finite Element Analysis (FEA) is used in the design and development of a wide range of applications by mechanical engineers. Engineering material studies cannot be justifiably performed without including an FEA method. This article covers the fundamentals of the FEA method, its applications, and its importance in engineering material studies.
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