Elements that have a negative impact on the performance and quality of steel mainly include the following:

Sulfur (S): Sulfur is one of the harmful elements in steel. It mainly exists in the form of sulfide in steel. Sulfur can cause the hot brittleness of steel to increase, that is, the toughness of steel at high temperatures is significantly reduced and brittle fracture is prone to occur. In addition, sulfur can also affect the weldability of steel and increase the risk of cracks in the weld.

Phosphorus (P): Phosphorus is also a harmful element in steel. It will reduce the toughness of steel, especially at low temperatures, making the steel prone to brittle fracture, that is, increased cold brittleness. Phosphorus also reduces the weldability of steel and adversely affects the corrosion and fatigue resistance of steel.

Oxygen (O): Although oxygen is inevitable in the steelmaking process, excessive oxygen content can have adverse effects on the properties of the steel. Oxygen combines with other elements in the steel to form oxide inclusions that reduce the purity and mechanical properties of the steel, especially fatigue strength and toughness.

Nitrogen (N): Nitrogen mainly exists in the form of interstitial solid solution in steel. It will increase the strength and hardness of steel, but it will also reduce the plasticity and toughness of steel. In some cases, nitrogen can also cause increased age brittleness of steel.

Hydrogen (H): Hydrogen can easily form defects such as bubbles and looseness in steel, seriously affecting the mechanical properties and processing properties of steel. In addition, hydrogen can also cause hydrogen embrittlement of steel, that is, under the action of stress, hydrogen atoms will diffuse and gather at microscopic defects in the steel, thereby reducing the toughness of the steel and increasing the risk of brittle fracture.

Lead (Pb), tin (Sn), arsenic (As), antimony (Sb), bismuth (Bi): These elements will also have adverse effects on the performance of the steel when the content is high in the steel. They may reduce the steel's toughness, strength, corrosion resistance and processability, among other things.