Dimensional Metrology is the science of calibrating and using measuring equipment to determine the physical size or distance from an object. Inspection is a critical step in product development and quality control. Dimensional Metrology requires the use of a variety of physical scales to determine dimension, with the most accurate of these being laser interferometers and encoders. The realization of dimension using these accurate scale technologies is the end goal of dimensional metrologists.

The pressure is defined as the physical force exerted on an object. The force applied is perpendicular to the surface of objects per unit area. The basic formula for pressure is F/A (Force per unit area). Unit of pressure is Pascals (Pa). Types of Pressures are Absolute, Atmospheric, Differential, and Gauge Pressure.

Mass:

The mass of an object is a fundamental property of the object; a numerical measure of its inertia; a fundamental measure of the amount of matter in the object. Definitions of mass often seem circular because it is such a fundamental quantity that it is hard to define in terms of something else. All mechanical quantities can be defined in terms of mass, length, and time. The usual symbol for mass is m and its SI unit is the kilogram. While the mass is normally considered to be an unchanging property of an object, at speeds approaching the speed of light one must consider the increase in the relativistic mass.

Mechanical Balance:

The balance (also balance scale, beam balance and laboratory balance) was the first mass measuring instrument invented. In its traditional form, it consists of a pivoted horizontal lever with arms of equal length – the beam – and a weighing pan suspended from each arm. The unknown mass is placed in one pan and standard masses are added to the other pan until the beam is as close to equilibrium as possible. In precision balances, a more accurate determination of the mass is given by the position of a sliding mass moved along a graduated scale. Technically, a balance compares weight rather than mass, but, in a given gravitational field (such as Earth’s gravity), the weight of an object is proportional to its mass, so the standard masses used with balances are usually labeled in units of mass.

Electronic Devices – Microbalance

A microbalance or ultra-microbalance are instruments capable of making precise measurements of mass of objects of relatively small mass of the order of a million parts of a gram and below.

Acceleration:

Acceleration is the rate of change of the velocity of an object with respect to time. Accelerations are vector quantities. The orientation of an object’s acceleration is given by the orientation of the net force acting on that object

Speed :

Rotational speed or speed of revolution) of an object rotating around an axis is the number of turns of the object divided by time, specified as revolutions per minute (rpm), cycles per second (cps), radians per second (rad/s), etc.

Force:

Force is any interaction that, when unopposed, will change the motion of an object. A force can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a push or a pull. A force has both magnitude and direction, making it a vector quantity. It is measured in the SI unit of Newton and represented by the symbol F.

Universal Testing Machine:

Uniaxial testing machine also known as Universal Testing Machine (UTM) , is used to test the tensile stress, compressive strength of materials. It is named after the fact that, it can perform any standard tensile and compressive tests on materials, components and structures.

Hardness:

Hardness is a measure of the resistance to localized plastic deformation induced by either mechanical indentation or abrasion. Some materials (e.g. metals) are harder than others (e.g. plastics, wood). Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, there are different measurements of hardness: scratch hardness, indentation hardness, and rebound hardness.

Indentation Hardness :

Brinell Hardness Testing Machine

The Brinell Scale characterizes the indentation hardness of materials through the scale of penetration of an indenter, loaded on a material test-piece.

Rockwell Hardness Testing Machine:

The Rockwell Scale is a hardness scale based on indentation hardness of a material. The Rockwell test determines the hardness by measuring the depth of penetration of an indenter under a large load compared to the penetration made by a preload. There are different scales, denoted by a single letter, that use different loads or indenters. The result is a dimensionless number noted as HRA, where A is the scale letter.

Vickers Hardness Testing Machine:

Vickers is as an alternative to the Brinell method to measure the hardness of materials. The Vickers test is often easier to use than other hardness tests since the required calculations are independent of the size of the indenter, and the indenter can be used for all materials irrespective of hardness. The unit of hardness given by the test is known as the Vickers Pyramid Number (HV) or Diamond Pyramid Hardness (DPH).