Based on the brittle tempering temperature range of precision steel tubes, it can be divided into low-temperature temper brittleness (cold brittleness) and high-temperature temper brittleness. What are the factors that affect the precision cold-drawing tube cold brittle? Our analysis has the following three aspects:

1. Solid solution strengthening elements. Phosphorus increases toughness-brittle transition temperature is very strong; there are molybdenum, titanium and vanadium; when the content is low, the impact is not high, but when the content is high, the toughness is increased; the brittle transition temperature is silicon, chromium, and copper; the toughness-brittleness conversion is reduced. The temperature of nickel, first reduced and then increased the toughness of a brittle transition temperature of manganese.

2. Form the elements of the second phase. The second phase adds the most important element of cold-rolled precision bright steel cold-brittle as carbon. As the carbon content in the cold-rolled precision bright steel pipe increases, the pearlite content in the cold-rolled precision bright steel pipe increases, and the average pearlite volume increases by 1%. The toughness-brittle transition temperature increased by an average of 2.2°C. Effect of Carbon Content on Brittleness of Ferrite - Pearlitic Steels . The microalloying elements such as titanium, niobium, and vanadium are added to form diffusely distributed nitrides or carbonitrides, causing the toughness-brittle transition temperature of cold-rolled precision bright steel tubes to rise.

3. The grain size affects the toughness-brittle transition temperature. With the grain coarsening, the toughness-brittle transition temperature increases. Refinement of grains reduces cold and brittle tendency of cold-rolled precision bright steel tubes, which is a widely used method.