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       1. Solid solution strengthening elements. Phosphorus increases the toughness-to-brittleness transition temperature strongly; there are also molybdenum, titanium and vanadium; elements that have little effect when the content is low but increase the toughness-to-brittleness transition temperature when the content is high include silicon, chromium and copper; elements that lower the toughness-to-brittleness transition temperature include nickel, and manganese that first lowers and then increases the toughness-to-brittleness transition temperature.

       2. Elements that form two phases. increase in two phasesHigh precision cold drawn tubeThe most important element in cold brittleness is carbon. As the carbon content in the product increases, the pearlite content in the product increases. On average, for every 1% increase in pearlite volume, the ductility-brittleness transition temperature increases by an average of 2.2°C. It is the effect of carbon content in ferrite-pearlitic steel on brittleness. Adding micro-alloying elements such as titanium, niobium and vanadium forms dispersed nitrides or carbonitrides, causing the ductility-brittleness transition temperature of the product to increase.

       3. The grain size affects the toughness-to-brittleness transition temperature. As the grains coarsen, the toughness-to-brittleness transition temperature increases. Refining the grains reduces the cold brittleness tendency of high-precision cold drawn tubes, which is a widely used method.