Materials and Constraints

The 5 Exterior Forces Tension Compression Torsion Shearing Bending

Constraints effects caused inside a material by an external force which tends to deform it Application of the force application of the force of tensionthe effects of an identical force of compressionwill not be the same if the thickness is different

Types of Constraints ConstraintDefinitionExamples TensionTensile stress is formed in a material which undergoes a force tending to lengthen it CompressionCompressive stress is formed in a material which undergoes a force tending to compress it TorsionTorsional stress is formed in a material which undergoes a force tending to twist it

Deformations Elastictemporary change in dimensions of a part when it put there under constraint. The object regains its shape as soon as the force is released Plasticpermanent deformation which occurs at the time of a setting under constraint and which remains when the force causing the deformation is removed

Mechanical Properties of Materials characteristic specific to a material. It can determine the way in which the material will act or react under one or more mechanic pressures

Principle Mechanical Properties of Materials PropertyDefinition Hardnesscapacity to resist the deformation during the penetration of a hard body Rigiditycapacity to resist traction (tension) Impact Strengthcapacity to resist shocks Malleabilitycapable of being flattened into thin sheets without tearing, under the effect of a compressive force such as hammering or rolling

Principle Mechanical Properties of Materials PropertyDefinition Brittlenessfact of breaking without becoming deformed under the effect of a force has little tendency to deform (or strain) before fracture Ductilitycapacity to be able to be stretched into wire without breaking under the effect of a force of traction Elasticitycapacity of an object to regain its initial shape when the force which acts on it ceases

Principle Mechanical Properties of Materials PropertyDefinition Thermal Conductibility capacity to transmit heat Thermal Dilation Coefficient property characterizing the relative increase in the volume of a body according to the increase in the temperature Corrosion Resistance capacity to resist the action of smoke, salts and chemicals which cause corrosion (rust)