THE EFFECT OF SHEET THICKNESS TO FORMABILITY USING HYPERFORM FATIN ZULAIKHA BINTI MOHD HATANAN

Transcription

1 THE EFFECT OF SHEET THICKNESS TO FORMABILITY USING HYPERFORM FATIN ZULAIKHA BINTI MOHD HATANAN B.ENG (HONS.) MANUFACTURING ENGINEERING UNIVERSITI MALAYSIA PAHANG i

2 THESIS STATUS VALIDATION FORM UNIVERSITI MALAYSIA PAHANG DECLARATION OF THESIS AND COPYRIGHT Author s full name : FATIN ZULAIKHA BINTI MOHD HATANAN Date of Birth : 07/01/1993 Title : THE EFFECT OF SHEET THICKNESS TO FORMABILITY USING HYPERFORM Academic Session : SEMESTER 2, 2015/2016 I declare that this thesis is classified as: CONFIDENTIAL RESTRICTED OPEN ACCESS (Contains confidential information under the Official Secret Act 1977)* (Contains restricted information as specified by the organisation where research was done)* I agree that my thesis to be published as online open access (Full text) I acknowledge that Universiti Malaysia Pahang reserve the right as follows: 1. The Thesis is the Property of Universiti Malaysia Pahang. 2. The Library of Universiti Malaysia Pahang has the right to make copies for the purpose of research only. 3. The Library has the right to make copies of the thesis for academic exchange. Certified By: (Student s Signature) (Supervisor s Signature) Assoc Prof Ahmad Razlan Bin Yusoff New IC/Passport Number Name of Supervisor Date: 20 JUNE 2016 Date: 20 JUNE 2016 NOTES : * if the thesis is CONFIDENTIAL or RESTRICTED, please attach with the letter from the organisation with period and reasons for confidential or restriction. ii

3 THE EFFECT OF SHEET THICKNESS TO FORMABILITY USING HYPERFORM FATIN ZULAIKHA BINTI MOHD HATANAN Thesis submitted in fulfillment of the requirements for the award of the degree of Bachelor of Manufacturing Engineering Faculty of Manufacturing Engineering UNIVERSITI MALAYSIA PAHANG JUNE 2016 ii

4 SUPERVISOR S DECLARATION I hereby declare that I have checked this thesis and in my opinion, this thesis is adequate in terms of scope and quality for the award of the degree of Bachelor s Degree (Hons) of Manufacturing Engineering. ( Supervisor s Signature) Full Name : ASSOC. PROF. DR. AHMAD RAZLAN BIN YUSOFF Position : ASSOCIATE PROFESSOR/DEPUTY DEAN ACADEMIC & STUDENT AFFAIRS Date : 20 JUNE 2016 iii

5 STUDENT S DECLARATION I hereby declare that the work in this thesis is based on my original work except for quotations and citation which have been duly acknowledged. I also declare that it has not been previously or concurrently submitted for any other degree at Universiti Malaysia Pahang or any other institutions. (Author s Signature) Full Name : FATIN ZULAIKHA BINTI MOHD HATANAN ID Number : FA Date : 20 JUNE 2016 iv

6 TABLE OF CONTENTS DECLARATION Page TITLE PAGE SUPERVISOR S DECLARATION STUDENT S DECLARATION SPECIAL DEDICATION ACKNOWLEGEMENTS ABSTRACT ABSTRAK TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES LIST OF ABBREVIATIONS i ii iii iv v vi vii viii xi xii xiv CHAPTER 1 INTRODUCTION 1.1 Project Background Problem Statement Research Aim & Objectives Scopes Of Study Flowchart 4 CHAPTER 2 LITERATURE REVIEW 2.1 Introduction Advanced High Strength Steel Types of AHSS Ferritic-Bainitic (FB) Steel Sheet Metal Forming Processes of Sheet Metal Forming Factor influencing Sheet Metal Forming Effect of Sheet Metal Thickness 15 viii

7 2.5 Formability Stress and strain relationship Young's modulus, E Yield strength, σy Ultimate Tensile Strength Fracture Strength Formability Test Types of Defect Blank Holder Blank Holder Pressure Blank Holder Force Metal Flow Forming Limit Diagram Concept of Forming Limit Diagram Calculation for Forming Limit Diagram Finite Element Analysis Application of FEM in Metal Forming Finite Element Software Finite Element Simulation Summary 31 CHAPTER 3 METHODOLOGY 3.1 Introduction Material Design Of Model Development of 3D Model Design Parameters Selection Table of Experiment Finite Element Simulation Material Model Element Difference between Shell and Solid Elements Type of Analysis 40 ix

8 3.7 Summary 40 CHAPTER 4 RESULTS ANALYSIS AND DISCUSSIONS 4.1 Introduction Punch And Die Clearance Forming Limit Curve Forming Limit Diagram Finite Element Simulation Blank holder force Design of experiment Summary 51 CHAPTER 5 CONCLUSION AND RECOMENDATIONS 5.1 Introduction Conclusion Recommendation 53 REFERENCES 54 APPENDICES A Gantt Chart for FYP 56 B Die Opening for Different Sheet Thicknesses 58 C Material Creation in Hyperform Material Database 60 D Results of FLD Diagram 61 x

9 LIST OF TABLES Table Title Page 2.1 Steel type designators First generation and the second generation of AHSS General characteristics of sheet metal forming operation Chemical composition of SPH590-SF Mechanical Properties of SPH590-SF Tool geometry parameters Process parameter Design of experiment Die opening for different thicknesses Colour scheme indication on FLD Design of experiment results 48 xi

10 LIST OF FIGURES Figure Title Page 1.1 Purpose of sheet metal application Project flow chart Formability chart, presenting the assortment of properties exist from recent AHSS FB 450/600 Photomicrograph Lower arm of Toyota Vios Illustration of Stress-Strain Diagram Determination of yield point on a) mild steel and b) low and high alloy steels at 0.2% offset Risks of rupture on FLD Flat areas in FLD Wrinkling risk on FLD Schematic illustration of metal flow in cup Image of forming limit diagram for the sheet metal forming Schematic illustration of Forming Limit Diagram by Keeler and Goodwin Sample of circle grid of FLD test: (a) The condition before deformation is occurred; (b) The condition after deformation is occurred Illustration of condition of circle grid: (a) Drawing region; (b) Stretch region Basic steps to conduct a representative FE simulation Methodology chart Shape of initial sheet Model of hemispherical cup Shell element and solid elements 39 xii

11 4.1 Die opening for sheet with 1mm thick Effect of sheet thicknesses on the forming limit curve FLC0 of various sheet thicknesses Simulation for thickness 3mm with BHF 10kN Simulation for thickness 3mm with BHF 150kN Simulation for thickness 3mm with BHF 160kN Simulation for thickness 3mm with BHF 200kN Blank holder force of differences sheet thicknesses Maximum % thinning vs sheet thickness Minimum % thinning vs sheet thickness 50 xiii

12 LIST OF ABBREVIATIONS AHSS BHF DOE FB FE FEA FLC Advanced High Strength Steel Blank holder force Design of experiment Ferritic Bainitic Finite element Finite element analysis Forming limit curve FLC0 Forming Limit Curve of minor strain 0 FLD FYP UTS Forming limit diagram Final year project Ultimate tensile stress xiv