Dissertation > Excellent graduate degree dissertation topics show

Failure Analysis and Processing Technology Improvement of the Bicycle Flywheel Parts and Its Molding Die

Author: LiWei
Tutor: LiuQingSuo
School: Tianjin University of Technology
Course: Materials Science
Keywords: Cold extrusion dies 14th flywheel gear teeth chip Microstructure Microhardness Stress accumulation Fracture failure
CLC: U484
Type: Master's thesis
Year: 2011
Downloads: 63
Quote: 0
Read: Download Dissertation


The to multi the Feifei wheel core cold to a bicycle Group extrusion mold punch and the Group's production of the 14 - tooth flywheel teeth as the research object , using optical microscopy , scanning electron microscopy and micro-hardness measurement analysis of the bike the cold extrusion punch and 14 tooth chip multi Feifei wheel core fracture Failure and production mold process Chainrings parts improvement measures . Punch for Feifei round round core cold extrusion , the microstructure observed apparent uneven zonal distribution of carbide in the microstructure of the failure die ; fracture morphology and crack near the EDS test analysis showed carbide centralized area for fracture crack occurred . Uneven banded carbide mold organization of the underlying causes of the fracture failure , mold formed in the cold extrusion process stress accumulated mold Fracture Failure in the carbide concentrated area external incentives . Suggestions : ① into the factory mold raw materials change forging handling . ( 2 ) mold quenching , tempering temperature were adjusted to 1210 ℃ and 560 ℃ . ③ the use of the process of extrusion parts about 3500 , remove the punch , 280 ℃ to stress tempering 2h . 14th tooth flywheel the Chainrings parts of the nitrided layer and the carbon content distribution characteristics of comparison with Japan Xi Manuo products , results show that for cold extrusion molding blanks bike flywheel teeth , because the Chainrings teeth from tooth top to the tooth root , the deformation state of each region is different, direct carburization treatment , corresponding to each region of the nitrided layer is not uniform , and the surface in the carburization treatment under conditions of high carbon potential easily formed mainly from brittle carbide phase having a bright white areas ( that over the infiltration area ) , in particular, that the tooth root area nitrided layer the seepage zone size and microhardness value is too high to become a major source area of the parts by force fracture . Recommendation : ① on the the cold extrusion teeth piece before Carburizing an annealing process , the annealing temperature of 650 ℃, holding time 10min . ② carburization process , the beginning , the end of the carbon potential is adjusted to 0.85 and 0.80 ( C %) .

Related Dissertations

  1. Reactive Hot-Pressing and Mechanical Properties of (ZrB2-ZrO2)/BN Composites,TB332
  2. Microstructure and Mechanical Properties of Mg-Zn-Y-Zr Alloys,TG146.22
  3. Investigation on Microstructure and Properties of Cadmium-Free Silver-Based Intermediate Temperature Filler Metals,TG425.2
  4. Research on Technology and Mechanism of Joining Cemented Carbide to Carbon Steel,TG454
  5. The Investigations on the Characteristics and Mechanism of NIR Emission from Bi-doped Silicophosphate Glasses,TQ171.1
  6. Preliminary Study on Salt-Tolerant Mechanism of the New Pennisetum Purpereum Schumach Variety-Sumu No.2,S543.9
  7. Study on the Fine Structure of Intestine and Intestinal Mucosal Barrier in Zebrfish (Brachydanio Rerio),Q95-33
  8. Study on Characteristics of Morphology Anatomy and Physio-Biochemistry of Two Ecotype Varieties Cucumber Leggy Seedilings,S642.2
  9. Study on the Mechanism of Heat-Induced Gelation of Myofibrillar Proteins,TS251.1
  10. Studies on the Aggregation and Microstructure of Imidazolium Ionic Liquids in Solutions,O645.1
  11. Research Physiological Response and Antioxidative Mechanism of Wheat (Triticum Aestivum L.) Seedings under Copper or Cadmium Stress,S512.1
  12. Studies of Luminescence Characteristics of Eu3+-doped Rare Earth Borates REBaB9O16 (RE=rare Earth Ions and Y),O627.3
  13. The Research on Extrusion Parameters Through the Plate Billet of Magnesium Alloy,TG379
  14. Study on Stock Price Behavior Around Periodical Reports Based on Asymmetric Information,F832.51
  15. Research on Processings and Microstructure and Properties of HRB400MPa,TG335
  16. Study of Performance of Cordierite Combined Mullite Products,TQ175.71
  17. Effect of Adding ZrO 2 Nanopowder on Microstructure and Mechanical Properties of Carbon Steel,TB383.1
  18. The Broussonetia papyrifera fiber structure and properties of microwave - assisted the degumming process parameters optimization,TS123
  19. Studies on the Influence of Rare Earth Ce on Microstructure and Properties of Huge Heat Input SAW Seam Metal,TG445
  20. Hexagonal boron nitride micro- structure and adsorption properties of,TB383.3
  21. Rolled Mg-Zn-Ce-Zr (Mn) alloy microstructure and mechanical properties of,TG339

CLC: > Transportation > Road transport > Other road transport > Bicycle
© 2012 www.DissertationTopic.Net  Mobile