Dissertation > Excellent graduate degree dissertation topics show

Research on the Relationship of the Mechanical Property and the Metallurgical Structure in Hot-rolled Strip

Author: MaZhengWei
Tutor: LiuBing
School: Xinjiang University
Course: Materials Processing Engineering
Keywords: Hot strip Mechanical Properties Inclusions Widmanstatten Banded structure
CLC: TG142.1
Type: Master's thesis
Year: 2009
Downloads: 215
Quote: 0
Read: Download Dissertation

Abstract


The market today are increasingly demanding quality requirements for steel , requires not only a good surface quality , microstructure, mechanical properties of steel put forward higher requirements . To find Q235B hot rolled wide strip steel cold-formed substandard performance and low elongation , in order to take appropriate measures to improve the smelting and rolling process , improve the quality of the steel , and start from the mechanical properties of the strip and organizational relationships using the macroscopic fracture analysis , spectral composition analysis , microhardness , metallographic analysis and other analytical tools to conduct a comprehensive physical and chemical testing . Meanwhile, in order to identify the J55 and the H40 oil casing steel welding cracks and welded pipe flattening cracking the reasons , in order to clarify the steel quality welding process to start to solve this problem , this paper through macro analysis , low magnification analysis , spectral composition analysis metallographic analysis , scanning electron microscopy spectroscopy detection means comprehensive tESTING . Q235B hot rolled wide strip , J55 and H40 oil casing steel production process to make improvements based on the analysis results , and trial production of hot-rolled plant in Shandong Taishan Iron and Steel Group . Studies have shown that the main reasons for failure of performance of Q235B Hot Strip Steel has two aspects: First, the high inclusions ; organization the Widmanstatten structure or granular bainite , is a typical fast-cooling organization reduce the plasticity , improve strength , resulting in the mechanical properties unqualified . Take measures to reduce the content of inclusions by the steelmaking process ; rolling process, to improve the finish rolling temperature to 880 ° C to 890 ° C ; increase the cooling intensity, improve the rolling speed, maintain temperature uniformity and other measures to obtain the organization of the steel strip the upper and lower surfaces the fast cold organization ( widmanstatten or granular bainite ) , Centre for normal annealing organizations to solve Q235B failed the mechanical properties of the strip . J55 and H40 oil casing steel welding cracks and welded pipe flattening cracking is the direct cause serious banded structure indirectly because of the high level of non-metallic inclusions , and number . Lower finish rolling temperature and rolling through the rolling process to take a front-end layer flow cooling measures may be appropriate to reduce the level of the banded structure .

Related Dissertations

  1. Reactive Hot-Pressing and Mechanical Properties of （ZrB2-ZrO2）/BN Composites,TB332
  2. Research on Welding Characteristics of CO2 Laser-GMA Hybrid Welding for Ultra-Low Carbon Bainitic Steel,TG456.7
  3. Microstructure and Mechanical Properties of Mg-Zn-Y-Zr Alloys,TG146.22
  4. Study on the Recycling of Post-Consumer Polyester Textiles,X791
  5. Fabricationand Properties of SiC-AlN Multiphase Ceramics Prepared by Gelcasting,TQ174.62
  6. Synthesis of Polysulfones and Modification for Epoxy Adhesives,TQ433.437
  7. Structure and Characterization of Room Temperature Self-crosslinked Acrylonitrile-butadiene-styrene,TQ325.2
  8. The Research on Extrusion Parameters Through the Plate Billet of Magnesium Alloy,TG379
  9. Modification of Talc Powder and Its Reinforcing and Toughening on Recycled Polypropylene,TQ325.14
  10. Effect of Adding ZrO 2 Nanopowder on Microstructure and Mechanical Properties of Carbon Steel,TB383.1
  11. Preparation of Surface-functionalized Graphene and Its Influence on the Mechanical Properties of Nanocomposite Materials,TB332
  12. Preperation of Low Friction and Wear Resistant High-Purity Alumina Ceramic,TQ174.1
  13. The Study of Forming Process and Properties of PTT/PET Skin-Core Composite Monofilament with Large Diameter,TQ340.64
  14. Research on Structure and Mechanical Property of Hook and Loop Fastener,TE931.2
  15. Studies on the Influence of Rare Earth Ce on Microstructure and Properties of Huge Heat Input SAW Seam Metal,TG445
  16. Rolled Mg-Zn-Ce-Zr (Mn) alloy microstructure and mechanical properties of,TG339
  17. Simulated lunar ambient temperature magnesium alloy microstructure and mechanical properties of,TG146.22
  18. Shanghai Comprehensive Test of mechanical properties of clay and constitutive modeling,TU411.3
  19. A Study on the Fullerene Nanocomposites,TB383.1
  20. Triple-Wire High Speed GMAW Butt Joint Welding Process of Marine E Grade Steel,TG457.11
  21. Rinse jeans and Shade on physical and mechanical properties of Research,TS190.1

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metallurgy and Heat Treatment > Metallic materials > Steel > Microstructure and properties of steel
© 2012 www.DissertationTopic.Net  Mobile