The influencing mechanisms of banded structure, nonmetallic inclusions and grain size on transverse impact toughness are systematically analyzed aiming at such problems as great fluctuation of transverse impact property and unstable low-temperature toughness of H beam SM490YB for ocean engineering. The Mn segregation and spheroidized inclusions are effectively inhibited, grains are refined as well as microstructure homogenization is realized through adopting such comprehensive measures as composition optimization, modified inclusions with Ca treatment, low superheat continuous casting as well as controlled rolling and cooling. The transverse impact energy at -20 ℃ is improved, fluctuation is reduced, banded structure is improved, spheroidization effect of inclusions are obvious and grains are refined for H beam with specification of H300×300 with treatment of optimum technology.

Under the background of national strategy of “east data, west computing”, Baotou Steel Group actively promotes the construction of data center relying on its energy and regional advantages. In this paper, it is introduced the technical architecture and construction practices of data center of Baotou Steel Group, analyzed its technical solutions from such aspects as green energy saving, integration of storage and computing and information technology application innovation cloud platform, summarized the application effects of data center in such fields as intelligent manufacturing and data governance as well as discussed the challenges facing and countermeasures for future development. The experiences of constructing data center of Baotou Steel Group could provide references for similar enterprises.

The rectification of audit is the “second half” of audit supervision in state-owned enterprises, the “last kilometer” to realize achievement transformation of audit as well as key link of maintaining the safety of state-owned assets and promoting high quality development of state-owned enterprises. In the paper, the prominent problems of ideological understanding, implementing responsibilities, mechanism construction, supervision collaboration and audit team construction in rectification of audit are analyzed by taking the requirements of closed-loop management system of auditing administration as guidance, combining with the regulations of Rectification and Implementation Measures for Problems Identified in Audit issued by the Audit Office of Inner Mongolia Autonomous Region, basing on the characteristics of large asset scale, multi-level supervision, long business chains and great social responsibilities of state-owned enterprises as well as focusing on their actual situations. Moreover, the optimization strategies are proposed from such five dimensions as implementing responsibilities, perfecting regimes, enabling technologies, establishing collaborative mechanisms and audit team construction, which could provide references for state-owned enterprises to achieve the goal of “rectifying one problem, perfecting one regime and governing one field”.

As a kind of revolutionary metal protection material, the Zn-Al-Mg coated steel has become the upgraded substitute of traditional zinc-plating material due to its excellent corrosion resistance, self-repairing capability and good processing performance. In this paper, it is systematically overviewed the research status, market analysis, technological progress and development trends of Zn-Al-Mg coated steel at home and abroad. Firstly, it is emphatically analyzed the progress of such key technologies as the composition design, performance optimization, mechanism of corrosion resistance, life model, technological breakthrough of welding and processing as well as environment friendly surface treatment technologies. Secondly, the application status of Zn-Al-Mg coated steel in such fields as photovoltaic industry, automobile and construction is discussed as well as future development trends towards high strength, light weight, environmental protection and intelligentization are proposed aiming at such challenges facing by the industry as non-uniform technical standards and cost pressure. Finally, the suggestions on healthy development of Zn-Al-Mg coated steel industry in our country are put forward.

The steel is the core in modern industrial system and its surface quality influences performances and service life of products. In this paper, it is focused on the research on detection technologies for surface defects of steel, systematically introduced common types of surface defects and their formation mechanisms, comprehensively analyzed advantages and disadvantages of traditional detection methods, elaborated the principles, application results and challenges facing of emerging detection technologies represented by machine vision and deep learning as well as deeply discussed the defect repair technologies and surface quality control strategies. The research showed that the detection precision and efficiency were significantly improved with the emerging detection technologies, but they need to be improved from such aspects as adaptability in complicated industrial environment. In the future, the detection technologies for surface defects of steel will be developed towards the directions of multi-technology fusion, intelligence and standardization to meet the increasing industrial production requirements.

The epoxy resin is with the characteristics of high specific stiffness and specific strength so that it is widely used in such fields as the aerospace, automobile, construction and electronics. Its main disadvantage is brittleness so that the bending property of composite using it as the matrix is reduced. It is one approach for effectively solving this problem to use nano materials as the filler of epoxy resin. Therefore, the effects of hybrid filler composed of metallic nanoparticles and inorganic nanomaterials added into epoxy resin on bending property of epoxy resin matrix are mainly studied in this paper. The Fourier transform infrared spectroscopy (FTIR) test results showed that the hybrid filler composed of nano-Ti, nano-MoS₂ and carbon nanofibers (CNFs) was physically adhered with epoxy resin matrix so that the bending property of epoxy resin matrix was significantly improved. The hybrid filler is prepared with nano materials of four different weight percentages (2%, 4%, 6% and 8%). Among these, the enhancement effect of hybrid filler with 4% of nano materials on bending property of epoxy resin matrix is optimum. The morphology characterization of crimped section is carried out with scanning electron microscope (SEM). The synergetic enhancement effects of different metallic nanoparticles and inorganic nano materials on resin matrix are deeply analyzed in this paper, which is hopeful to provide guidance for improving the bending property of resin matrix composite.

The industrial trial production of S420MLO hot-rolled high-strength low temperature resistant H beam for ocean engineering is carried out by Baotou Steel based on the industrial tests. The results showed that the yield strength of test steel was greater than 450 MPa and with certain surplus, its tensile strength was 615~628 MPa, average yield ratio was 0.75, elongation could reach over 26% as well as impact energy at -40 ℃ could meet standard requirement so that it is with excellent strength and toughness. The microstructure of test steel is mainly composed of ferrite and pearlite, the nano precipitated phase in matrix is with length of 100 nm and width of 20~30 nm, which could significantly improve the properties of steel. The S420MLO hot-rolled high-strength low temperature resistant H beam developed is with excellent comprehensive properties, which could provide the solid material support for safe service of such equipment as ocean platforms.

The microstructure of rail could be changed as well as mechanical properties, wear resistance and fatigue resistance of rail are significantly improved with heat treatment process so that service life of rail is increased. The online heat treatment process of remaining heat quenching has become the important part in production process of rail due to its advantages such as high efficiency and energy conservation. In the paper, it is discussed the effects of such key control factors in heat treatment process of rail as the stability of chemical compositions, heating and soaking processes of billet, online cooling process, equipment accuracy and process assembly quality on microstructure and various properties of rail in detail. The quality stability of rail could be guaranteed through the fine control of influence factors, which could meet the demands of modern railway constructions.

The factors influencing vibration accuracy are found out aiming at the problem of deterioration of synchronism for vibration table of 2-stream crystallizer for CSP continuous casting machine. The target of recovering vibration accuracy is achieved by such measures as replacing the hinge joint bearing of link mechanism for vibration table, adjusting elevation of base for link mechanism of vibration table and coping standard station of installing crystallizer on vibration table.

In order to meet the requirements of steel for engineering structures with high strength, high toughness and good welding performance for bridge, the trial production of Q345qE hot rolled H section steel is carried out by Baotou Steel. It is successfully completed through strictly performing the process parameter requirements of the whole process of smelting, refining, continuous casting and hot rolling. The chemical components of trial-produced steel could meet the requirements of GB/T 714—2015 Steel for Bridge Structures, its yield strength is 417~419 MPa, tensile strength is 533~538 MPa, elongation is 28.5%~33.0% and low-temperature impact energy (-40 ℃) is 178~201 J so that all indexes could meet the standard requirements. The comprehensive performances of steel are stable, which could provide the technical support for industrial productions and applications of bridge engineering of Q345qE hot rolled H section steel.