Dissertation > Excellent graduate degree dissertation topics show

Development of Rolling and Heat Treatment Process of 9Ni Steel

Author: YangZhe
Tutor: WangGuoDong；LiuZhenYu
School: Northeastern University
Course: Materials Processing Engineering
Keywords: 9Ni steel Composition design Rolling process Heat treatment process Mechanical Properties Parameter optimization
CLC: TG161
Type: Master's thesis
Year: 2008
Downloads: 185
Quote: 1
Read: Download Dissertation

Abstract


With the increasing awareness of environmental protection, LNG (liquefied natural gas) as a clean energy source, the proportion of occupied more and more, so developers have independent intellectual property rights in China LNG structural materials - 9Ni low temperature steel is imminent. In this paper, the mechanical properties of 9Ni steel Evaluation through ingredient Design, thermal simulation and experiment of rolling process, heat treatment process, and analyze their microstructure and mechanical properties of various processes, optimization of process parameters. The content and the results of the study include: the Reference at home and abroad on 9Ni steel composition standards, optimize the parameters of its components, and provide a valid basis for industrial production; thermal simulation testing machine to carry hot deformation experiments 9Ni steel. Single-pass compression test, different temperatures, different deformation rate conditions 9Ni steel austenitic stress - strain relations derived deformation resistance model; 9Ni steel static and dynamic CCT curve measured by continuous cooling test results show that: bainite transformation region exists only in the 1 ° C / s - 30 ° C / s cooling conditions compared with the static and dynamic bainite transition temperature is lower, end of the transition temperature is higher, the transition speed is high, i.e. a Bayesian a smaller area of ​​the body; simulated die casting and continuous casting and rolling austenite region final rolling process, two new process is based on trying to achieve the purpose of production reduction: continuous casting and rolling of biphasic District final rolling process and on-line heat treatment process. The test results show that: the two new rolling technology to produce 9Ni steel exhibit good mechanical properties; 4. Explore the 9Ni steel components, and finish rolling temperature of its mechanical properties, the results show that: Ni content affect significantly , high and low when the mechanical properties are inferior; finish rolling temperature was 730 ℃, the organization is small, good mechanical properties; changed by the heat treatment test the temperature of the various stages of parameters, optimizing the heat treatment program to analyze the heat treatment at the same time each stage The temperature parameters of the organization and the low-temperature toughness. The results show that: the process parameters to optimize the transfer of heat treatment (QT) to 800 ℃ quenching and tempering at 580 ℃, the quenching temperature affect the grain size, The tempering temperature affects the amount of precipitation and reversed austenite stability; optimize the heat treatment of the two-phase region (QLT ) process parameters 580 ℃ to 800 ℃ quenching 670 ℃ intermediate quenching tempering, quenching temperature effect is not obvious, the tempering temperature affects the amount of precipitation and reversed austenite stability; better after the QLT After 9Ni steel low temperature toughness.

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. Hot air drying characteristics of lettuce osmotic dehydration mass transfer kinetics and permeability,TS255.52
  8. Structure and Characterization of Room Temperature Self-crosslinked Acrylonitrile-butadiene-styrene,TQ325.2
  9. The Research on Extrusion Parameters Through the Plate Billet of Magnesium Alloy,TG379
  10. Modification of Talc Powder and Its Reinforcing and Toughening on Recycled Polypropylene,TQ325.14
  11. Effect of Adding ZrO 2 Nanopowder on Microstructure and Mechanical Properties of Carbon Steel,TB383.1
  12. The Studies on Some Improvements of the GA and Their Applications in SVM,TP18
  13. The Study of Forming Process and Properties of PTT/PET Skin-Core Composite Monofilament with Large Diameter,TQ340.64
  14. A Study on the Fullerene Nanocomposites,TB383.1
  15. Polymer modified cement-based repair materials research,U414
  16. Study on Mechanical Performance of Curved Box-girder with Corrugated Steel Webs,U448.213
  17. Mechanical Properties Analysis and Optimum Design of the Super-span Suspension Bridge with CFRP Cables,U448.25
  18. The Application of the Cold Recycled of Cement Mixture in the Repair Works of Asphalt Pavement,U414
  19. Analysis of Parameter Calculation and Optimization in Vibration Isolation System Based on Genetic Algorithm,TB535.1
  20. Research on the Fatigue Behavior of Magnesium Alloy Treated by Laser Shot Peening Based on Numerical Analysis and Experiment,TN249
  21. Studying on Degumming Process and Research of Structure and Properties of Corn Husk Fiber,TS102.2

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metallurgy and Heat Treatment > Heat treatment > Heat treatment of steel
© 2012 www.DissertationTopic.Net  Mobile