3results about How to "Improve crack arrest performance" patented technology

The invention discloses a hot rolling process method for large-wall-thickness acid-resistant pipeline steel X70MS with good low-temperature drop weight performance. The hot rolling process method is characterized in that the pipeline steel comprises the following chemical components in percentage by mass: 0.03%-0.04% of C, 0.2%-0.4% of Si, 1.0%-1.2% of Mn, 0.3%-0.5% of Cr, 0.3%-0.4% of Cu, 0.3%-0.5% of Ni, 0.10%-0.25% of Mo, 0.03%-0.04% of Nb, 0.01%-0.015% of Ti, 0.005%-0.008% of Ce, less than or equal to 0.004% of S, less than or equal to 0.008% of P and the balance of Fe and inevitable impurities. A continuous casting billet with the thickness of 360 mm or above is adopted for production, and the thickness of a finished product is 40-55 mm; a three-stage rolling process and a matched intermediate billet cooling and after-rolling ultra-fast cooling process are adopted, and the produced pipeline steel has good low-temperature plastic deformation performance and good hydrogen induced cracking resistance.

This invention discloses a layered concrete structure with anti-penetration and filtering properties and its preparation method. It solves the problem in existing technologies where only the composition of the concrete layers is changed without improving the overall filtering performance. This invention has the beneficial effects of improving filtering performance and preventing further crack development. The specific solution is as follows: A layered concrete structure with anti-penetration and filtering properties includes a fiber-reinforced concrete layer and an intermediate composite material layer. The intermediate composite material layer is placed between two fiber-reinforced concrete layers. The fiber-reinforced concrete layer and the intermediate composite material layer are periodically arranged to form a layered concrete structure to enhance the filtering performance and improve the anti-penetration performance. The fiber-reinforced concrete layer contains steel fiber reinforcement to enhance the anti-penetration performance of the layered concrete structure. The wave transmittance in the intermediate composite material layer is different from that in the fiber-reinforced concrete layer, and the intermediate composite material layer is bonded to the fiber-reinforced concrete layer.

The invention discloses a high fracture toughness flux-cored wire for ocean engineering, which comprises a carbon steel sheath and powder filled in the sheath, and is characterized in that the powder comprises non-metal powder and metal powder; the non-metal powder comprises the following components in parts by weight: 360-380 parts of titanium dioxide; 13 to 25 parts of quartz; 40 to 50 parts of potassium silicotitanate; 35 to 55 parts of sodium silicotitanate; and 13-18 parts of cryolite. The welding wire is suitable for multi-layer and multi-pass welding of an EH36 steel plate with the thickness of 80 mm; and the welding heat input is controlled to be 12-25 kJ / cm, and good process adaptability is achieved.