Abstract
The invention discloses an atmosphere corrosion resistance seamless steel tube containing rare earth and a production method thereof, and belongs to the technical field of metallurgy and molding. The atmosphere corrosion resistance seamless steel tube comprises the materials by weight percent (Wt%): 90% of blast furnace liquid iron and 10% of excellent steel scrap, and the chemical ingredients of a tube blank comprise the following chemical components by weight percent (Wt%): 0.05-0.10% of C, 0.10-0.30% of Si, 1.30-1.60% of Mn, not more than 0.020% of P, not more than 0.005 of S, 0.20-0.50% of Cr, 0.10-0.30% of Mo, 0.20-0.40% of Ni, 0.30-0.50% of Cu, 0.05-0.20% of V, 0.01-0.03% of Ti, 0.01-0.04% of Al, 0.0005-0.0100% of RE, and the balance of Fe and non-detectable microelements. The preparation method comprises the technological processes of: preprocessing of molten iron, top and bottom combined-blowing converter smelting, LF furnace refining, VD vacuum treatment, continuously casting of a round billet, cutting, heating of the tube blank, perforating, continuously rolling, reheating, coining (reducing tension), straightening, cooling, cutting via a saw, and flaw detection; the mechanical properties of the steel tube are as follows: the yield strength is 460-520 MPa; the tensile strength is 600-660 MPa; the yield ratio is smaller than or equal to 0.80; the elongation percentage is greater than or equal to 25%; the transverse impact value is greater than or equal to 100J / cm<2> (0 DEG C); the shear ratio is 100%; the grain size is greater than or equal to 8.5 grades; the hardness is smaller than or equal to 21.0 HRC (rockwell hardness); the residual stress is smaller than or equal to 30 MPa. The product disclosed by the invention has the characteristics of high hardness matching degree, small grain size and good air-corrosion resistance.
Description
1. Technical field:
[0001] The invention belongs to the field of ferrous metal smelting and metal pressure processing, and relates to a rare earth-containing non-quenched and tempered seamless steel pipe resistant to atmospheric corrosion and a production method thereof. 2. Background technology:
[0002] my country's climate is complex and changeable, and a lot of steel is scrapped due to atmospheric corrosion every year. For this reason, atmospheric corrosion-resistant steels have been developed successively at home and abroad. The application of these materials can effectively prevent the damage of atmospheric corrosion to steel. This type of steel is mainly plates and profiles, and seamless steel pipes are not involved. For this reason, the atmospheric corrosion-resistant seamless steel pipes are specially developed to meet the atmospheric corrosion resistance requirements of seamless steel pipes such as pipelines, oil derricks and construction machinery.
[0003] After ...
