You should follow the following steps:

The samples should be grinded using 100, 200, 400, 600, 800, 1000,1200,1500, 2000 grit silicon carbide paper one after the other in the mentioned order. Each phase of the sample preparation must be executed cautiously and surface free of scratch can be obtained by engaging a sequence of consecutively finer abrasives grades. Special care must be taken to apply uniform pressure during manual grinding.

After grinding, the samples should be polished using polishing cloth laden with some suitable abrasive i.e. SiC . Diamond paste generally of 0.1- 0.5 µm particle size with desired lubricant can be employed for obtaining mirror finish surface. The samples should be free of any type of mould.

Steps to be followed in the preparation of the sample for SEM are as follows :

1) sample preparation & cleaning : prepare the sample using a operation like milling keeping in view the size, shape, state, and conductivity. Clean it thoroughly with suitable agent/s to free it from any extraneous matter.

2) sample fixation and dehydration : use a suitable agent like glutaldehyde and dehydrate using a dehydrating agent like alcohol such that water vapour doesn't interfere the electron beam.

3) sample drying : dry the sample thoroughly by freeze or air drying.

4) sample stubs, adhesives and mounting approach : use sample stubs or supports likr clean forceps or gloves for handling and double coated carbon tape as an adhesive to mount the sample such that conductive path exists for the sample in question.

5 ) sample storage : store the sample in clean & dry environment.

Dear Sir. Concerning your issue about the steps involved in sample preparation for SEM . The welded joints were sliced using power hacksaw and then machined to the required dimensions for preparing tensile specimens. Transverse tensile specimens were prepared

to obtain the tensile properties of the joints. ASTM E8M-04 (ASTM 2004) guidelines were followed for preparing the test specimens. Smooth (unnotched) tensile specimens were prepared to evaluate transverse tensile properties of the joints such as yield strength, tensile strength, and percentage of elongation. Notched tensile specimens were prepared to evaluate notch tensile strength and notch strength ratio. I think the following below links and the attached file may help you in your analysis:

https://www.research.manchester.ac.uk/portal/files/63039028/FULL_TEXT.PDF https://www.sciencedirect.com/science/article/pii/S2214785317304613

Thanks