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Principles of welding : processes, physics, chemistry, and metallurgy /

"Despite the critically important role welding plays in nearly every type of human endeavor, most books on this process either focus on basic technical issues and leave the science out, or vice versa. In Principles of Welding, industry expert and prolific technical speaker Robert W. Messler, Jr...

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Detalles Bibliográficos
Clasificación:	Libro Electrónico
Autor principal:	Messler, Robert W., Jr., 1942-
Formato:	Electrónico eBook
Idioma:	Inglés
Publicado:	New York : John Wiley, Ã1999.
Edición:	1st ed.
Temas:	Welding. Soudage. welding. Schweiėn
Acceso en línea:	Texto completo

Tabla de Contenidos:

I. THE PROCESS AND PROCESSES OF WELDING
II. THE PHYSICS OF WELDING
III. THE CHEMISTRY OF WELDING
IV. THE METALLURGY OF WELDING.
I. THE PROCESS AND PROCESSES OF WELDING
1. INTRODUCTION TO THE PROCESS OF WELDING
1.1. What Is Welding?
1.2. The Evolution of Welding as a Process
1.3. The Nature of an Ideal Weld: Achieving Continuity
1.4. Impediments to Making Ideal Welds in the Real World
1.5. What It Takes to Make a Real Weld
1.6. Advantages and Disadvantages of Welding
1.7. Summary
2. CLASSIFYING WELDING PROCESSES
2.1. Why Classify Processes?
2.2. Mechanisms for Obtaining Material Continuity
2.3. The Roles of Temperature and Pressure
2.4. Alternative Bases for Classification
2.4.1. Fusion Versus Nonfusion
2.4.2. Pressure Versus Nonpressure
2.4.3. Energy Sources for Welding
2.4.4. Interface Relationships and Classification by Energy Transfer Processes
2.4.5. Other Bases for Classification and Subclassification
2.5. Allied Processes
2.6. The AWS Classification Scheme
2.7. Summary
3. FUSION WELDING PROCESSES
3.1. General Description of Fusion Welding Processes
3.2. Chemical Fusion Welding Processes
3.2.1. Oxyfuel Gas Welding
3.2.2. Aluminothermic Welding
3.3. Electric Arc Welding Processes
3.3.1. Nonconsumable Electrode Arc Welding Processes
3.3.1.1. Gas-Tungsten Arc Welding
3.3.1.2. Plasma Arc Welding
3.3.1.3. Magnetically Impelled Arc Butt Welding
3.3.2. Consumable Electrode Arc Welding Processes
3.3.2.1. Gas-Metal Arc Welding
3.3.2.2. Shielded-Metal Arc Welding
3.3.2.3. Flux-Cored Arc Welding
3.3.2.4. Submerged Arc Welding
3.3.2.5. Electrogas Welding
3.3.2.6. Electroslag Welding
3.4. Resistance Welding Processes
3.4.1. Resistance Spot, Resistance Seam, and Projection Welding
3.4.2. Flash, Upset, and Percussion Welding
3.5. High-Intensity Radiant Energy or High-Density Beam Welding Processes
3.5.1. High-Energy-Density (Laser and Electron) Beam Welding Processes
3.5.2. Focused IR and Imaged Arc Welding
3.5.3. Microwave Welding
3.6. Summary
4. NONFUSION WELDING PROCESSES
4.1. General Description of Nonfusion Welding Processes
4.2. Pressure (Nonfusion) Welding Processes
4.2.1. Cold Welding Processes
4.2.2. Hot Pressure Welding
4.2.2.1. Pressure Gas Welding
4.2.2.2. Forge Welding
4.2.3. Roll Welding
4.2.4. Explosion Welding
4.3. Friction Welding Processes
4.3.1. Radial and Orbital Welding
4.3.2. Direct-Drive Versus Inertia-Drive (Friction) Welding
4.3.3. Angular and Linear Reciprocating (Friction) Welding
4.3.4. Ultrasonic (Friction) Welding
4.3.5. Friction Stir Welding
4.3.6. Friction Surfacing
4.4. Diffusion Joining Processes
4.4.1. Diffusion Welding
4.4.1.1. Conventional Diffusion Welding
4.4.1.2. Deformation Diffusion Welding
4.4.1.3. Resistance Diffusion Welding
4.4.1.4. Continuous Seam Diffusion Welding
4.4.2. Diffusion Brazing
4.4.3. Combined Forming and Diffusion Welding
4.5. Solid-state Deposition Welding Processes
4.6. Inspection and Repair of Nonfusion Welds
4.7. Summary.
II. THE PHYSICS OF WELDING
5. ENERGY FOR WELDING
5.1. Introduction to the Physics of Welding
5.2. Sources of Energy for Welding
5.3. Source Energy, Transferred Power, Energy Density, and Energy Distribution
5.3.1. Energy Available at a Source (Energy Level or Capacity)
5.3.2. Transferred Power
5.3.3. Source Intensity or Energy Density
5.3.4. Energy Distribution
5.4. Energy Input to a Weld
5.5. Causes of Loss During Energy Transfer From Source to Work
5.6. Transfer Efficiency of Processes
5.7. Effects of Deposited Energy: Good and Bad
5.7.1. Desirable Melting, Fluxing, or Softening
5.7.2. Adverse Effects of Heat in and Around the Weld
5.8. Effects of Energy Density and Distribution
5.9. Summary
6. THE FLOW OF HEAT IN WELDS
6.1. General Description of the Flow of Heat in Welds
6.2. Weld Joint Configurations
6.2.1. Types of Weld Joints
6.2.2. General Weld Design Guidelines
6.2.3. Size of a Weld and Amount of Welding
6.3. The Welding Thermal Cycle
6.4. The Generalized Equation of Heat Flow
6.5. Analysis of Heat Flow During Welding
6.5.1. Rosenthal's Simplified Approach
6.5.2. Modifications to Rosenthal's Solutions
6.5.3. Dimensionless Weld Depth Versus Dimensionless Operating Parameter
6.6. Effect of Welding Parameters on Heat Distribution
6.7. Prediction of Weld Zones and Weld Cooling Rates
6.7.1. Zones in Fusion-Welded Materials
6.7.2. Simplified Equations for Approximating Welding Conditions
6.7.2.1. Peak Temperatures
6.7.2.2. Width of the Heat-Affected Zone
6.7.2.3. Solidification Rate
6.7.2.4. Cooling Rates
6.8. Weld Simulation and Simulators
6.9. Summary
7. THERMALLY INDUCED DISTORTION AND RESIDUAL STRESSES DURING WELDING
7.1. Origin of Thermal Stresses
7.2. Distortion Versus Residual Stresses
7.2.1. Causes of Residual Stresses in Weldments
7.2.1.1. Residual Stresses From Mismatch
7.2.1.2. Residual Stresses From Nonuniform, Nonelastic Strains
7.2.2. Causes of Distortion in Weldments
7.3. Typical Residual Stresses in Weldments
7.4. Effects of Distortion
7.5. Effects of Residual Stresses
7.6. Measurement of Residual Stresses in Weldments
7.6.1. Stress-Relaxation Techniques
7.6.1.1. A Sectioning Technique Using Electric-Resistance Strain Gauges
7.6.1.2. The Rosenthal-Norton Section Technique
7.6.1.3. The Mathar-Soete Hole Drilling Technique
7.6.1.4. The Gunnert Drilling Technique
7.6.2. The X-ray Diffraction Technique
7.7. Residual Stress Reduction and Distortion Control
7.7.1. The Interplay Between Residual Stresses and Distortion
7.7.2. Prevention Versus Remediation
7.7.3. Controlling or Removing Residual Stresses
7.7.4. Controlling or Removing Distortion
7.8. Numerical Methods for Estimating Residual Stresses
7.9. Summary.
8. THE PHYSICS OF WELDING ENERGY OR POWER SOURCES
8.1. Electricity for Welding
8.2. The Physics of an Electric Arc and Arc Welding
8.2.1. The Physics of an Electric Arc
8.2.1.1. The Welding Arc
8.2.1.2. The Arc Plasma
8.2.1.3. Arc Temperature
8.2.1.4. Arc Radiation
8.2.1.5. Arc Electrical Features
8.2.1.6. Effect of Magnetic Fields on Arcs
8.2.2. Volt-Ampere Characteristics for Welding
8.2.2.1. Constant-Current Power Sources
8.2.2.2. Constant-Voltage Power Sources
8.2.2.3. Combined Characteristic Sources
8.3. The Physics of a Plasma
8.4. The Physics of Resistance (or Joule) Heating and Resistance Welding
8.4.1. Joule Heating
8.4.2. The Resistance Welding Cycle
8.4.3. Resistance Welding Power Supplies
8.5. The Physics of Electron Beams
8.5.1. Electron-Beam Generation
8.5.2. Electron-Beam Control
8.5.3. Role of Vacuum in EB Welding
8.5.4. Electron-Beam-Material Interactions
8.6. The Physics of Laser Beams
8.6.1. Laser Light
8.6.2. Laser Generation
8.6.2.1. Nd:YAG Lasers
8.6.2.2. CO2 Lasers
8.6.3. Laser-Beam Control
8.6.4. Laser-Beam-Material Interactions
8.6.5. Benefits of Laser-Beam and Electron-Beam Welding
8.7. The Physics of a Combustion Flame
8.7.1. Fuel Gas Combustion or Heat of Combustion
8.7.2. Flame Temperature
8.7.3. Flame Propagation Rate or Combustion Velocity
8.7.4. Combustion Intensity
8.8. The Physics of Converting Mechanical Work to Heat
8.9. Summary
9. MOLTEN METAL TRANSFER IN CONSUMABLE ELECTRODE ARC WELDING
9.1. Forces Contributing to Molten Metal Transfer in Welding
9.1.1. Gas Pressure Generation at Flux-Coated or Flux-Cored Electrode Tips
9.1.2. Electrostatic Attraction
9.1.3. Gravity
9.1.4. Electromagnetic Pinch Effect
9.1.5. Explosive Evaporation
9.1.6. Electromagnetic Pressure
9.1.7. Plasma Friction
9.1.8. Surface Tension
9.2. Free-Flight Transfer Modes
9.2.1. Globular Transfer
9.2.2. Spray Transfer
9.3. Bridging of Short-circuiting Transfer Modes
9.4. Pulsed-Arc or Pulsed-Current Transfer
9.5. Slag-Protected Transfer
9.6. Variations of Major Transfer Modes
9.7. Effect of Welding Process Parameters and Shielding Gas on Transfer Mode
9.7.1. Effects on Transition Current
9.7.2. Shielding Gas Effects
9.7.3. Process Effects
9.7.4. Operating Mode or Polarity Effects
9.8. Summary
10. WELD POOL CONVECTION, OSCILLATION, AND EVAPORATION
10.1. Origin of Convection
10.1.1. Generalities on Convection in Weld Pools
10.1.2. Buoyancy or Gravity Force
10.1.3. Surface Gradient Force or Marangoni Convection
10.1.4. Electromotive Force or Lorentz Force
10.1.5. Impinging or Friction Force
10.1.6. Modeling Convection and Combined Force Effects
10.2. Effects of Convection
10.2.1. Effect of Convection on Penetration
10.2.2. Effect of Convection on Macrosegregation
10.2.3. Effect of Convection of Porosity
10.3. Enhancing Convection
10.4. Weld Pool Oscillation
10.5. Weld Pool Evaporation and Its Effects
10.6. Summary.
III. THE CHEMISTRY OF WELDING
11. MOLTEN METAL AND WELD POOL REACTIONS
11.1. Gas-Metal Reactions
11.1.1. Gas Dissolution and Solubility in Molten Metal
11.1.2. Solid Solution Hardening and Phase Stabilization
11.1.3. Porosity Formation
11.1.4. Embrittlement Reactions
11.1.5. Hydrogen Effects
11.1.5.1. Hydrogen Embrittlement
11.1.5.2. Hydrogen Porosity
11.1.5.3. Hydrogen Cracking
11.2. Molten Metal Shielding
11.2.1. Shielding Gases
11.2.2. Slags
11.2.3. Vacuum
11.2.4. Self-Protection and Self-Fluxing Action
11.3. Slag-Metal Reactions
11.3.1. Deoxidizing/Denitriding (or Killing) Versus Protection
11.3.2. Flux-Protected Welding Processes
11.3.3. Shielding Capacities of Different Processes
11.3.4. Slag Function
11.3.5. Slag-Metal Chemical Reactions
11.3.6. Flux Types
11.3.7. Common Covered- and Cored-Electrode Flux Systems
11.3.7.1. Shielded Metal Arc Welding Electrode Coatings
11.3.7.2. Flux-Cored Arc Weldipg Fluxes
11.3.7.3. Submerged Arc Welding Fluxes
11.3.8. Basicity Index
11.3.9. Thermodynamic Model for Welding Slag- Metal Reactions
11.4. Summary
12. WELD CHEMICAL HETEROGENEITY
12.1. Weld (Pool) Dilution
12.2. Microsegregation and Banding in the Weld Metal
12.3. Unmixed and Partially Mixed Zones
12.4. Impurities in the Weld Metal
12.5. Macrosegregation in Dissimilar Welds
12.6. Summary
IV. THE METALLURGY OF WELDING
13. WELD FUSION ZONE SOLIDIFICATION
13.1. Equilibrium Versus Nonequilibrium
13.2. Solidification of a Pure Crystalline Material
13.2.1. Criteria for Equilibrium at TE, and Constant Pressure
13.2.2. Pure Material Growth Modes
13.2.3. Homogeneous Versus Heterogeneous Nucleation
13.2.3.1. Homogeneous Nucleation
13.2.3.2. Super- or Undercooling
13.2.3.3. Effect of Radius of Curvature on Supercooling
13.2.3.4. Heterogeneous Nucleation
13.2.4. Epitaxial and Competitive Growth
13.2.5. Effect of Weld Pool Shape on Structure
13.2.6. Competing Rates of Melting and Solidification
13.2.7. Effect of Nonequilibrium on Pure Material Solidification
13.3. Equilibrium Solidification of an Alloy
13.3.1. Prerequisites for the Solidification of Alloys
13.3.2. Equilibrium Solidification of a Hypothetical Binary Alloy (Case 1)
13.4. Nonequilibrium Solidification of Alloys
13.4.1. Boundary Conditions for Solidification of Alloys
13.4.2. Equilibrium Maintained Throughout the System at all Times: Microscopic Equilibrium (Case 1)
13.4.3. Complete Liquid Mixing/No Diffusion in the Solid (Case 2)
13.4.3.1. Expression for the Composition of Solid at the Advancing Solid-Liquid Interface
13.4.3.2. Calculation of the Average Composition of the Solid for Case 2
13.4.4. No Liquid Mixing/No Diffusion in the Solid (Case 3)
13.4.4.1. Trace of Average Composition in the Solid for Case 3
13.4.4.2. Expression for the Initial Transient in the Composition of the Solid Formed
13.4.4.3. Some Limitations of the Classic Models
13.4.5. Other Effects of Rapid Solidification
13.4.5.1. Nonequilibrium Solute Partitioning
13.4.5.2. Nonequilibrium Phases
13.5. Consequences of Nonequilibrium Solidification
13.5.1. Interdendritic Microsegregation
13.5.2. Solidus Suppression
13.5.3. Substructure Formation
13.5.3.1. Constitutional Supercooling
13.5.3.2. Effect of Cooling Rate on Substructure
13.5.3.3. Interface Stability
13.5.3.4. Nucleation of New Grains Within the Fusion Zone
13.5.3.5. Controlling Substructure
13.5.4. Centerline Segregation
13.6. Fusion Zone Hot Cracking
13.6.1. Mechanism of Hot Cracking
13.6.2. Remediation of Hot Cracking
13.6.2.1. Control of Weld Metal Composition
13.6.2.2. Control of Solidification Structure
13.6.2.3. Use of Favorable Welding Conditions
13.7. Summary.
14. EUTECTIC, PERITECTIC, AND POSTSOLIDIFICATION FUSION ZONE TRANSFORMATIONS
14.1. Eutectic Reactions or Solidification of Two-Phase Alloys
14.1.1. Solidification at the Eutectic Composition
14.1.2. Solidification of Two-Phase Alloys at Noneutectic Compositions
14.1.3. Morphology of Eutectic Phases
14.2. Peritectic Reactions
14.2.1. Equilibrium Conditions (Case 1)
14.2.1.1. Alloys Below the Solubility Limit of the Solid Phase in the Peritectic
14.2.1.2. Alloys Between the Solubility Limit and the Peritectic Composition
14.2.1.3. Alloys Wlth the Perltectlc Composltlon.
14.2.1.4. Alloys Beyond the Peritectic Composition, but Within the L + S Range.
14.2.1.5. Alloys Past the L + S Range of a Peritectic in the Liquid Field
14.2.2. Nonequilibrium Conditions
14.2.2.1. No Diffusion in the Solid/Complete Mixing in the Liquid (Case 2).
14.2.2.2. No Diffusion in the Solid/No Mixing, Only Diffusion in the Liquid (Case 3).
14.3. Transformations in Ferrite + Austenite or Duplex Stainless Steels
14.4. Kinetics of Solid-state Phase Transformations: Nonequilibrium Versus Equilibrium
14.5. Austenite Decomposition Transformations
14.5.1. Equilibrium Decomposition to Ferrite + Pearlite (The Eutectiod Reaction)
14.5.2. Nonequilibrium Decomposition to Other Ferrite Morphologies (Very Slow to Moderately Slow Cooling Rates)
14.5.3. Nonequilibrium Transformation to Bainite (Faster Cooling Rates)
14.5.4. Nonequilibrium Transformation to Martensite (Very Fast Cooling Rates)
14.6. Sigma and Chi Phase Formation
14.7. Grain Boundary Migration
14.8. Summary
15. THE PARTIALLY MELTED ZONE
15.1. Origin and Location of the Partially Melted Zone
15.2. Constitutional Liquation
15.3. Defects Arising in the PMZ
15.3.1. Conventional Hot Cracking and Liquation Cracking in the PMZ
15.3.2. Loss of Ductility in the PMZ
15.3.3. Hydrogen-Induced Cracking in the PMZ
15.4. Remediation of Defects in the PMZ
15.5. Summary.
16. THE WELD HEAT-AFFECTED ZONE
16.1. Heat-Affected Zones in Welds
16.2. The HAZ in Work-Hardened or Cold-Worked Metals and Alloys
16.2.1. The Physical Metallurgy of Cold Work/Recovery/Recrystallization/Grain Growth
16.2.2. Cold-Worked Metals and Alloys in Engineering
16.2.3. Avoiding or Recovering Property Losses in Work-Hardened Metals or Alloys
16.2.4. Development of a Worked Zone in Pressure-Welded Materials
16.3. The HAZ in a Solid-Solution-Strengthened Metal or of an Alloy
16.3.1. The Physical Metallurgy of Solid-Solution Strengthening or Alloying
16.3.2. Major Engineering Alloys Consisting of Single-Phase Solid Solutions
16.3.3. Maintaining Properties in Single-Phase Solid-Solution-Strengthened Alloys
16.4. The HAZ in Precipitation-Hardened or Age-Hardenable Alloys
16.4.1. The Physical Metallurgy of Precipitation- or Age-Hardenable Alloys
16.4.2. Important Precipitation-Hardenable Alloys in Engineering
16.4.3. Avoiding or Recovering Property Losses in Age-Hardenable Alloys
16.5. The HAZ in Transformation-Hardenable Alloys.
16.5.1. The Physical Metallurgy of Transformation-Hardenable Alloys
16.5.2. Some Important Engineering Alloys Exhibiting Transformation Hardening
16.5.3. Welding Behavior of Carbon and Alloys Steels
16.5.3.1. Behavior of Carbon Steels
16.5.3.2. Behavior of Alloy Steels
16.6. The HAZ in Corrosion-Resistant Stainless Steels
16.6.1. The Physical Metallurgy of Stainless Steels
16.6.2. Major Stainless Steels Used in Engineering
16.6.3. Sensitization of Austenitic Stainless Steels by Welding
16.6.4. Welding of Ferritic and Martensitic Stainless Steels
16.7. The HAZ in Dispersion-Strengthened or Reinforced Alloys
16.8. HAZ Defects and Their Remediation
16.8.1. Liquation Cracking
16.8.2. Reheat or Strain-Age Cracking
16.8.3. Quench Cracking and Hydrogen Cold Cracking
16.8.4. Weld Decay, Knife-Line Attack, and Stress Corrosion Cracking
16.8.5. Lamellar Tearing
16.9. Summary
17. WELDABILITY AND WELD TESTING
17.1. Weldability Testing
17.2. Direct Weldability or Actual Welding Tests
17.2.1. Fusion and Partially Melted Zone Hot-Cracking Tests
17.2.1.1. Finger Test
17.2.1.2. Houldcroft and Battelle Hot-Crack Susceptibility Tests
17.2.1.3. Lehigh Restraint Test
17.2.1.4. Variable-Restraint (or Varestraint) Test
17.2.1.5. Murex Hot-Cracking Test
17.2.1.6. Root-Pass Crack Test
17.2.1.7. Keyhole-Slotted-Plate Test
17.2.1.8. Navy Circular-Fillet-Weldability (NCFW) Test
17.2.1.9. Circular-Groove Cracking and Segmented-Groove Tests
17.2.1.10. Circular-Patch Test
17.2.1.11. Restrained-Patch Test
17.1.1.12. Sigmajig Test
17.2.2. Heat-Affected Zone General Cold-Cracking Weldability Tests
17.2.3. Hydrogen Cracking Testing
17.2.3.1. Implant Test
17.2.3.2. RPI Augmented Strain Cracking Test
17.2.3.3. Controlled-Thermal-Severity (CTS) Test
17.2.3.4. Lehigh Slot Weldability Test
17.2.3.5. Wedge Test
17.2.3.6. Tekken Test
17.2.3.7. Gapped-Bead-on-Plate or G-BOP Test
17.2.4. Reheat or Strain-Age Cracking Test
17.2.4.1. Compact Tension Test
17.2.4.2. Vinckier Test
17.2.4.3. Spiral Notch Test
17.2.5. Lamellar Tearing Tests
17.2.5.1. Lehigh Cantilever Lamellar Tearing Test
17.2.5.2. Tensile Lamellar Tearing Test
17.3. Indirect Weldability Tests or Tests of Simulated Welds
17.4. Weld Pool Shape Tests
17.5. Weld Testing
17.5.1. Transverse- and Longitudinal-Weld Tensile Tests
17.5.3. Bend Ductility Tests
17.5.2. All-Weld-Metal Tensile Tests
17.5.4. Impact Tests
17.5.5. Other Mechanical Tests
17.5.6. Corrosion Tests
17.5.6.1. General Corrosion and Its Testing
17.5.6.2. Crevice Corrosion and Its Testing
17.5.6.3. Pitting Corrosion and Its Testing
17.5.6.4. Intergranular Corrosion and Its Testing
17.5.6.5. Stress Corrosion and Its Testing
17.6. Summary.

Principles of welding : processes, physics, chemistry, and metallurgy /

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