Following are the different tests that are performed:
1) Temper Test:
Standard: IS 1993- 1982
Take the sample strip of 90mm width.
Carry out the ‘zero setting’ on Erichsen Testing machine. After zero setting, clamp the dial by tightening the screw.
Insert the sample strip in machine and lock it by test piece holder.
Confirm the light arrangement and the mirror is placed on its respective position.
Switch on the lamp.
Rotate the back screw at uniform speed, so that the advanced punch can create uniform cup shape on test piece.
Hand wheel is to be rotated till the crack is observed.
Record the Erichsen value (cupping value) indicated on the scale.
Remove the sample strip by loosening the back screw.
Note the temper as per the thickness of the sheet/strip and cupping value, as per the table. (Note: Our desired temper value for the Tin sheet is T57 so the cupping value on the scale of the machine should lie in between 7.0 to 7.5)
2) Bend Test:
Standard: IS: 9025- 1978
A test specimen approximately 60mm long x 12mm wide is cut using sharp hand shear to avoid excess burring or necking of the edges. The specimen is hold vertically in two jaws of the vice and bend at 90° and alternately it is bend at 180° till the end point is reached at the first sign of fracture through the tin plate. The no. of bends to produce this fracture is recorded as the bending value.
Accomplish test involves taking two specimens cut with their long edges parallel and perpendicular to an edge of the tin plate sheet. These bending values are matched with the given table.
3) Scratch Test:
Standard: As per BS-3900 (Part- E2/IS-101-1984)
The automatic scratch tester is most suitable for research work or for the larger laboratory where repetitive quality control tests are carried out and the hand operated model is suitable for general laboratory test and with care consistent result can be obtained.
Hand operated:
The apparatus consists