Mild steel is a carbon steel with a carbon content below 0.25%, which is soft due to its low strength and hardness. It is also known as soft steel. The annealed microstructure of low-carbon steel is ferrite and a small amount of pearlite, with lower strength and hardness, and better plasticity and toughness. Therefore, its cold formability is good, and methods such as curling, bending, and stamping can be used for cold forming. This type of steel also has good weldability. Low carbon steel with a carbon content ranging from 0.10% to 0.30% is easy to accept various processes such as forging, welding, and cutting, and is commonly used in the manufacturing of chains, rivets, bolts, shafts, etc.

    QMAXIS provides the following plan for the preparation of low-carbon steel metallographic samples for your reference.

Photos of microstructure of low-carbon steel under 80X bright field after erosion with a 2% nitric acid alcohol solution

    The specific preparation steps for low-carbon steel samples are as follows:

    Cutting: QMAXIS metallographic cutting machine, with grinding wheel blades selected for cutting materials with a hardness range of HRC35

    Embedding: Hot press inlay machine, using QMAXIS black phenolic resin powder as the inlay material

    Mechanical sample preparation: Metpol-A

    Note: Comp. refers to the rotation of the sample fixture and the grinding disc in the same direction, Contra refers to the reverse rotation of the sample fixture and the grinding disc

    Etching: Use a 2% nitric acid alcohol solution for etching

    Attention: When polishing with diamond polishing paste/liquid, add QMAXIS DiaFluid water-based polishing lubricant as a lubricant and dispersant. After each polishing step, it is necessary to clean with alcohol or distilled water and dry the sample with compressed air. After the nitric acid alcohol solution corrodes, the sample needs to be washed clean with distilled water first, then cleaned with anhydrous alcohol, and dried with compressed air or a hair dryer.

    Can the above preparation methods help you solve the sample preparation problem? For more technical guidance, please contact QMAXIS customer service or application engineers.