Khurram Sayed and Saquib Fayyaz Magoon Said that, After our Several Meetings with SRB in good atmosphere with positive notes , We were expecting that, in this provincial budget 2016-17 service tax would be removed from Indentors
, but we wondered that, Sindh Govt kept old status regarding service tax on Indentors
Ltd; Japan) and a linear motor guide to transfer the motor rotation to the linear movement of the indentor
Even if penetration does not occur, the indentor
approaches the substrate sufficiently closely to be affected by that substrate and so the measured values often lay between the hardness of the two materials.
He grasps the indentor
across the palm of his other hand, with the tip emerging below the little finger.
The method used to measure hardness involves embedding a specific size and shaped indentor
into the surface of the test material, using a predetermined load or weight.
The Knoop hardess test determines the hardness from the resistance of metal to indentation by a pyramidal diamond indentor
with edged angles of 170 [degrees] 30 min and 130 [degrees] which makes a rhomboid impression with one long and one short diagonal.
This method is based on the penetration of a specific type of indentor
pushed into the specimen by a specific dead weight; the test instrument is called a durometer (figure 2), hence the term durometer hardness.
5 mm/min using a spherical steel indentor
of diameter 5 mm driven by an Instron 1185 mechanical testing machine.
Microhardness by Vickers method was determined on transverse sections using an optic microscope Polyvar Met, equipped with an attachment for measurement of hardness at 5 g load to indentor
and 10 s loading duration.
Conventional test methods utilized to quantify the scratch resistance were measurements such as: reduction in gloss of a coating after being subjected to a traversing tangential load of known particle size abrasive (crockmeter test); measurement of damage depth and recovery of damage depth of a coating after exposure to a single point indentor
(nanoindentor (4,5)); or quantitative measurement of the fraction of elastic, viscoelastic creep, and fracture response of a coating after exposure to a single point indentor
(scanning probe microscope (6)).
The recognized tests for hardness of materials, Brinell, Rockwell, Vickers, etc, consist of applying known weights and specific indentor
shapes to the surface of material samples and measuring the resulting permanent indentations.
Durometers are used to measure the hardness of non-metallic materials, such as rubber, and work by measuring the penetration of the gauge's indentor
under the specific conditions of a given durometer standard.