The etched surface is examined to determine weld soundness. Discontinues such as cracks, porosity, incomplete fusion, slag inclusions and lack of pentration are evaluated.. Pls Subscribe and like my humble request (07-07-2022)
*Carbon and Low-Alloy Steels* Three acids will work to etch low carbon steel: nitric acid, ammonium persulfate, and iodide/potassium iodide. Mix as follows. Nitric Acid - mixture of 5 - 10% nitric acid with the balance being alcohol. Water will work, but alcohol is preferred. Ammonium Persulfate - Mix one part ammonium persulfate to nine parts water by weight. Apply with a cotton swab. Iodide and Potassium Iodide - Mix one part iodide, two parts potassium iodide and ten parts water by weight. Apply with a brush at room temperature. *Stainless Steel* For stainless steels stick with the following mixture. Apply at room temperature with a cotton swab or immerse the part in the solution. 200g ferric chloride (FeCl3) + 300mL nitric acid (HNO3) + 100mL water (H20)
