Determination of carbon content in iron, steel and alloy
The general rules and general regulations shall comply with GB 1467-78.
I Caustic asbestos absorption gravimetric method
1. Method summary
The specimen is heated and burned in a high-temperature furnace by oxygenating to oxidize carbon to carbon dioxide. After the mixed gas is desulfurized, the carbon dioxide is absorbed in an absorption bottle containing caustic asbestos of known weight and weighed. The increased weight of the absorption bottle is calculated as the carbon content in the specimen.
Application scope: This method is applicable to pig iron, carbon steel, alloy steel, superalloy, precision alloy and iron powder.
Determination scope: 0.10%~5.0%.
2. Reagents and apparatus
Caustic asbestos①: Solid form (10~20 meshes or 20~30 meshes).
Fluxes②.
Oxygen③.
Apparatus (see Figure 1).
Gas washing bottle: 3, of which (5) and (7) are empty, (6) contains potassium dichromate-saturated sulfuric acid solution [weigh 30g of potassium dichromate in a 600mL beaker, add 30 ~ 40mL of water, heat the breaker to dissolve the potassium dichromate, evaporate at low temperature until it is nearly dry and crystallized, add 500mL of sulfuric acid (specific gravity of 1.84), and slightly heat to dissolve the crystals], fill until it is about one third of the bottle height.
I Caustic asbestos absorption gravimetric method II Gas volumetric method III Determination of free carbon IV Tolerance of carbon content
