Dissertation > Excellent graduate degree dissertation topics show

Research on TMCP Process of a Grade Q390 Type HSLA Steel Plate

Author: WangPengFei
Tutor: ZhaoDeWen
School: Northeastern University
Course: Materials Processing Engineering
Keywords: high strength low-alloy stee precipitation strengthening fine grain strengthening cooling temperature final cooling temperature final rolling temperature controlled rolling and controlled cooling
CLC: TG142.33
Type: Master's thesis
Year: 2008
Downloads: 122
Quote: 1
Read: Download Dissertation

Abstract


Based on the research platform for steel grades design of the state key Laboratory of Rolling and Automation (Northeastern University) and Puyang Steel Corporation (Handan),this paper mainly studied on the controlled rolling and controlled cooling’s process parameters of high strength low-alloy steel whose yield strength is 390MPa and the effect of Nb’s precipitate on the products’mechanical properties.It was requested that Q390 had not only high strength but also good formability and impact property under low temperature.Reasonable composition is the basis to ensure the property of Q390,The author used microalloy steel containing Nb as the additive,and realized lower flow stress and higher strength by precipitation strengthening and fine grain strengthening in rolling process.This made it possible for mass production in Puyang Steel Corporation.Furthermore, the author studied on the process of Q390’s controlled rolling and controlled cooling,established reasonable rolling process suitable for field production and made industrial experiments of 390MPa’s steel.The experiments reached expected target,so that Puyang Steel Corporation had the ability to produce various specification of Q390.This paper mainly four items,as follows:(1) In the laborotary,the author researched the cooling speed and final cooling temperature’s effect on microstructure and properties of rolled piece.The reasonable rolling process were that:heating temperature was 1180℃;initial rolling temperature of rough rolling was 1050℃;initial rolling temperature of finish rolling was lower and between 840℃and 900℃;final rolling temperature was also lower and about 600℃;laminar cooling speed after rolling was 10~20℃/s,The author could obtain Q390E according to the above process.(2) This paper discussed the relationship between the grain’s size and the product’s mechanical properties.It found that mechanical properties increased with the decrease of the grain’s size.When the cooling speed is in the rang of 10℃/s~20℃/s,the product’s microsturcture and properties increased with the increase of cooling speed and increased with the decrease of final rolling temperature and final cooling temperature.Deformation between passes affected the mechanical properties.Therefore,increasing the deformation between passes could improve the austenite grains,refine grain,and improve strength and toughness.These were theoretical basis of producing Q390.(3) Based on two industrial experiments in the field,Puyang Steel Company conduct mass production.Finally,the factory realized the production and updating of Q390 by adding Nb to Q345 and using reasonable process of controlled rolling and controlled cooling.(4) The author adjusted alloying elements,improved the smelting process,and proposed preliminary process from smelting,rolling to producing.This process was used in Puyang Steel Company and made the strength increase up to 380MPa based on the initial composition Q345.This process not only saved the raw material and reduced cost,but also improve the technical level of high strength plate in hot rolling.

Related Dissertations

  1. Effect of mass concrete embedded cooling pipes,U445.57
  2. Study and Development of Produced Process for Ultrafine of the Low Carbon and Low Alloy Steels,TG335.62
  3. The Study on the Air System of Light Radtech for the Paper Dryer,TS803
  4. Influence of Microalloying on Microstructure and Properties of Rephosphorized Cold-rolled Structural Steel Sheet,TG113
  5. Research of High Temperature Deformation Behavior and Microstructure Control and Refinement Technology for Pipeline Steel,TG335
  6. Investigation on Forced Cooling Techniques of the Large Turbine,TK261
  7. Investigation on Properties and Microstructure of Fire-resistant Construction Steel with Low-Mo Containing,TG142.7
  8. Basic technology of high strength pipeline X100,TG335.1
  9. Sensitive Analysis of Temperature Control Mesures of the Concrete Dam for Xiangjiaba Hydropower Station,TV544
  10. Study on Simulation of Concrete Crack Control of Soleplate in Sancha River of QinHuai River in NanJing,TV544
  11. Study on Unconfined Compression Test of Thawing Frozen Soil,TU413
  12. Development of High Strength Heavy Plate for Bridge Construction,TG335.5
  13. Research and Development of Low Cost and Ultra-fine Grain Weathering Steel,TG142.7
  14. Study on Microstructure and Property of Cold Rolled and Continuous Annealled DP Steel with Low C-Si-Mn System,TG142.1
  15. Temperature Measurement and Study on Quality Changes of Vacuum Cooled Horticultural Products,S609.3
  16. Solid-solution Aging and Electronic Structure of Mg-5wt%Sn Alloy,TG146.22
  17. Study on the Microstructures and Mechanical Properties and the Fracture Behavior of the Al-Zn-Mg-Cu-Zr Alloys,TG146.21
  18. Study on the Heat Transfer and the Thermal Stress in High-power Solid-State Lasers,TN248
  19. Study on Super High Managanese Steel with Trace Boron,TG142.33
  20. Study on Explosion Hardening Technology of Hadifield Steel,TG142.33

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metallurgy and Heat Treatment > Metallic materials > Steel > Variety of steel products : chemical composition distinguish > Alloy steel
© 2012 www.DissertationTopic.Net  Mobile