The 3 Properties of Fasteners

 There are 3 properties that contribute to the purpose of a fastener and what project it should be used for.  The three properties that give the fastener its abilities are:

·        Physical properties

·        Performance properties

·        Mechanical properties

Physical Properties

The physical properties are those that are unchanged or can only be altered slightly because they are natural in the raw material.  After manufacturing they are almost or exactly the same as in the original material.  Some of these qualities that are inherent in the raw material include: thermal conductivity, thermal expansion, magnetic susceptibility, density, and electrical resistivity.  They often contribute to fastener material selection and are all important factors.

Performance Properties

Performance properties are those that are built into the manufacturing of the fastener and are part of the functional design.  They are built in so as to gratify any requirements of the service application. By manipulating the manufacturing control of the product, the fastener gains characteristics like prevailing-torque, driving torque, sealing, and locking ability. Magnitude is influenced by choice of materials, as well as metallurgical treatment.  The performance properties are varied and change according to the needs of the fastener as determined by the design engineer.

Mechanical Properties

The reaction of a fastener to applied loads identified by the mechanical properties.  These are not usually the same as those of the raw properties that the fastener is made of.  Raw properties, like ductility and hardness are likely to change with the metallurgical treatments and manufacturing methods that are used.  Other mechanical properties include tensile strength, proof load, sheer strength, toughness, torsional strength, fatigue strength, and yield strength.  The post-treatment process and manufacturing determine the mechanical properties of a fastener.

These three properties contribute towards the cost of fasteners and the purpose.  When the three properties are combined they can also affect how the fastener can be used, the abilities, and they types of projects that it is suited for.  These are the factors that design engineers consider when they are making a fastener that is suitable for a specific need and purpose.