Check out our materials database with over common engineering materials! Metals are the most commonly used class of engineering material. The combination usually occurs through a process of melting, mixing, and cooling. The goal of alloying is to improve the properties of the base material in some desirable way.
Metal alloy compositions are described in terms of the percentages of the various elements in the alloy, where the percentages are measured by weight. Ferrous alloys have iron as the base element. These alloys and include steels and cast irons. Ferrous alloys are the most common metal alloys in use due to the abundance of iron, ease of production, and high versatility of the material.
The biggest disadvantage of many ferrous alloys is low corrosion resistance. Carbon is an important alloying element in all ferrous alloys. In general, higher levels of carbon increase strength and hardness, and decrease ductility and weldability. Carbon steels are basically just mixtures of iron and carbon. They may contain small amounts of other elements, but carbon is the primary alloying ingredient. The effect of adding carbon is an increase in strength and hardness.
Low-carbon steel has less than about 0. It is characterized by low strength but high ductility. Some strengthening can be achieved through cold working, but it does not respond well to heat treatment. Low-carbon steel is very weldable and is inexpensive to produce. Common uses for low-carbon steel include wire, structural shapes, machine parts, and sheet metal.
Medium-carbon steel contains between about 0. It can be heat treated to increase strength, especially with the higher carbon contents. Medium-carbon steel is frequently used for axles, gears, shafts, and machine parts. High-carbon steel contains between about 0.
It has high strength but low ductility. Common uses include drills, cutting tools, knives, and springs. The table below provides representative mechanical properties for several common carbon steels. Note 1. Low-alloy steels are typically stronger than carbon steels and have better corrosion resistance. Some low-alloy steels are designated as high-strength low-alloy HSLA steels. What sets HSLA steels apart from other low-alloy steels is that they are designed to achieve specific mechanical properties rather than to meet a specific chemical composition.
The table below provides representative mechanical properties for several common alloy steels. Tool steels are primarily used to make tooling for use in manufacturing, for example cutting tools, drill bits, punches, dies, and chisels. Alloying elements are typically chosen to optimize hardness, wear resistance, and toughness. Stainless steels have good corrosion resistance, mostly due to the addition of chromium as an alloying ingredient.Instructor for Structure and Bonding: Prof.
Nicola Marzari Instructor for Thermodynamics: Prof. Darrell Irvine. For most lectures, slides are presented below in two versions: the original slides, and annotated slides with in-class markup by the instructors. Don't show me this again. This is one of over 2, courses on OCW.
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Need help getting started? Don't show me this again Welcome! Fundamental Concepts PDF - 3. PDF - 1. Fundamental Concepts cont. PDF - 2.It is important to consider properties of materials such as density, and how materials react when forces are applied.
The image shows equal volumes of brass, balsa wood and polystyrene. How would their densities and masses compare? What could they be used for? The units of k are Nm The limit of proportionality is a point beyond which behaviour no longer conforms to Hookes law. The elastic limit is a point beyond which the spring will no longer return to its original shape when the force.
Elasticity is the ability to regain shape after deforming extension forces are removed.
A stretched or compressed material, like the spring in a jack-in-the-box when the lid is closed, has elastic potential energy EPE or elastic strain energy stored in it. According to the principal of conservation of energy, no energy is created or destroyed when a spring is compressed.
Therefore the work done in compressing the spring is equal to the EPE stored in it, plus any energy released as heat and sound. If the conversion of mechanical energy into thermal energy is ignored, work done is equal to EPE stored in the springs.
Stiffness reflects how difficult it is to change the shape or size of a material. Greater stiffness means a greater value for the force constant, k, and a steeper gradient of stressstrain curve representing the Young modulus. Strength refers to the ultimate tensile stress UTS.
A greater UTS means a stronger material. Toughness is a measure of the energy needed to break a material. Toughness is equal to the area under the stressstrain curve. However, it would only break under high stress, so the end-point of the line would be at a high y-value on the graph.
How would such a material behave under tensile testing and what would its stressstrain curve look like? How could the equipment could be used to find the Young modulus? Learn more about Scribd Membership Home. Read Free For 30 Days. Much more than documents. Discover everything Scribd has to offer, including books and audiobooks from major publishers. Start Free Trial Cancel anytime. Uploaded by diane hoyles.
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Is this content inappropriate? Report this Document.To browse Academia. Skip to main content. Log In Sign Up. Engineering properties of biological Materials.
Dinesh Chaudhary. Classification 1. Thermal properties such as specific heat, conductivity, diffusivity, and boiling point rise, freezing point depression. Electrical properties, primarily conductivity and permittivity. Structural and geometrical properties such as density, particle size, shape, porosity. Mechanical properties such as textural including strength, compressibility, and deformability and rheological properties such as viscosity.
Aerodynamic Properties such as terminal velocity. Specific heat, Cp, is the amount of heat needed to raise the temperature of unit mass by unit degree at a given temperature. Specific heat of solids and liquids depends upon temperature but is generally not sensitive to pressure.
Thermal conductivity represents the quantity of heat Q that flows per unit time through a food of unit thickness and unit area having unit temperature difference between faces; SI units are [W m— 1 K—1]. Electrical Conductivity is a measure of how well electric current flows through a food of unit cross-sectional area A, unit length L, and resistance R. Electrical permittivity is a dielectric property used to explain interactions of foods with electric fields.
It determines the interaction of electromagnetic waves with matter and defines the charge density under an electric field. Dielectric properties are also important in the selection of proper packaging materials and cooking utensils, and in the design of microwave and radio frequency heating equipment, because they describe how the material interacts with electromagnetic radiation. Porosity indicates the volume fraction of void space or air space inside a material.
Volume determination is relative to the amount of internal or closed or external or open pores present in the food structure. Therefore, like density, different forms of porosity are also used in food processing studies, namely open pore, closed pore, apparent, bulk, and total porosities.
Shrinkage is the reduction in volume or geometric dimensions during processing. Two types of shrinkage—isotropic and anisotropic—are usually observed in the case of food materials. Shrinkage occurs as a result of moisture loss during dryingice formation during freezingand formation of pores by drying, puffing, extrusion, and frying.
Roundness is a measure of the sharpness of the corners of a solid. Sphericity indicates how the shape of an object deviates from a sphere. Sphericity is defined from the volume, surface area, or geometric dimensions of an object. Texture can be defined as those physical characteristics arising from the structural elements of the food that are sensed primarily by the feeling of touch, related to deformation, disintegration, and flow of the food under a force, and measured objectively by functions of mass, time, and length.
This indicates that texture studies include structure molecular, microscopic, and macroscopic and the manner in which structure reacts to applied forces. Terminal velocity may be defined as equal to the air velocity at which a particle remains in suspended state in vertical pipe in the condition of free fall. The particle attains a constant terminal velocity Vv the net gravitational accelerating force Fg equals the resulting upward drag force Fr.To browse Academia.
Skip to main content. Log In Sign Up. James Mutua. MUTUA Course description Ferrous Alloys: Methods of production; iron-carbon phase diagram; types, properties, uses and heat treatment of plain carbon steels; Case hardening; stainless steel. Alloy steels; types, properties and uses. Cast Iron: Grey, white, ductile and malleable cast iron. Aluminium and its alloys: Methods of production of commercial aluminium, wrought and cast alloys; properties and uses.
Copper and its alloys: Methods of production of commercial copper, brasses, bronzes and cupro-nickel alloys; properties and uses. Special alloys: Characteristics and uses of nickel, titanium, magnesium, zinc alloys and refractory metals. Corrosion and degradation of materials: Oxidation; rates and mechanisms, designing against oxidation: Corrosion; electrochemical nature, types and prevention of corrosion. References 1. Pascoe, K. Jastrzebski, D.
MUTUA 1. What are the Responsibilities of Materials Engineer? Phase -1 of design process — Drawing the basic design. Phase -2 of design process — Selection of Proper Materials, i.
Proper choice selecting of substitute alternative materials when needed, 3. Contributing and Evaluating Materials tests results, 4. Studying and Composing Materials Data sheets before placing an order, 5. Doing Research Activities to enhance materials performance. This scheme is based primarily on chemical makeup and atomic structure, and most materials fall into one distinct grouping or another, although there are some intermediates.
In addition, there are three other groups of important engineering materials—composites, semiconductors, and biomaterials. Composites consist of combinations of two or more different materials, whereas semiconductors are utilized because of their unusual electrical characteristics; biomaterials are implanted into the human body.
A brief explanation of the material types and representative characteristics is offered next. Metals: these are materials whose valence electrons are delocalized and free to move in the crystal structure lattice.
Many properties of metals are directly attributable to these electrons. Ceramics: are compounds between metallic and nonmetallic elements; they are most frequently oxides, nitrides, and carbides. The wide range of materials that falls within this classification includes ceramics that are composed of clay minerals, cement, and glass. Polymers : Polymers include the familiar plastic and rubber materials.
Many of them are organic compounds that are chemically based on carbon, hydrogen, and other nonmetallic elements; furthermore, they have very large molecular structures. These materials typically have low densities and may be extremely flexible.Search this site.
Properties of Materials - Lesson plan and activity
About us. Automobile Engineering. Engineering Mechanics. Hydraulic Machines. Industrial Engineering. Machine Design. Manufacturing Technology. Power Plant Engineering. Strength Of Materials. Theory Of Machines. Disc Brake. Machineries used in Construction projects. Types of Brakes used in automobile. Engineering Materials And Their Properties. Classification of Engineering Mater ials 2. Weldability -ability of uniting two pieces of metal by applying pressure or heat or both.
03 Mechanical Properties of Materials.ppt
Elasticity -property due to which a metal regains its original dimension on removal of load. Plasticity -beyon elastic limit the material is unable to regain its original shape and retains to its moulded shape. Porosity -materials in their plastic or molten state contain some dissolved gasses which are evaporated once they are setformin gas holes and pores.
Hardness -ability of a material to resist penetration or scratching. Hardenability -ability of a material to be hardened by heat treat ment. Toughness -property of a material where it can absorb energy before actual fracture. Ductility -ability of a material to be drawn into wires. Fatigue - Resilience -property of a material to absorb energy within elastic range.After you enable Flash, refresh this page and the presentation should play.
Get the plugin now. Toggle navigation. Help Preferences Sign up Log in. To view this presentation, you'll need to allow Flash. Click to allow Flash After you enable Flash, refresh this page and the presentation should play. View by Category Toggle navigation. Products Sold on our sister site CrystalGraphics. Title: Properties and Selection of Engineering Materials. Ashby, Butterworth-Heinemann, Galvanic electrolytic chemistry. Coating, shape design.
Tags: engineering galvanic materials properties selection. Latest Highest Rated. Ashby, Butterworth-Heinemann, 2 2. Global view 16 E vs? Types of atomic bonding in polymers Effect of molecular weight and processing on Youngs modulus 18 Metals A given metal has a relatively narrow range in E and?
Nature of atomic bonding Relation with other properties. Whether your application is business, how-to, education, medicine, school, church, sales, marketing, online training or just for fun, PowerShow. And, best of all, most of its cool features are free and easy to use. You can use PowerShow. Or use it to find and download high-quality how-to PowerPoint ppt presentations with illustrated or animated slides that will teach you how to do something new, also for free.
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