ProgramMaster Logo
Conference Tools for 2023 AWS Professional Program
Login
Register as a New User
Help
Submit An Abstract
Propose A Symposium
Presenter/Author Tools
Organizer/Editor Tools
About this Abstract
Meeting 2023 AWS Professional Program
Symposium 2023 AWS Professional Program
Presentation Title Connecting X-ray Computed Tomography to Fatigue Life of Ti-6Al-4V using Quantitative Fractography
Author(s) Ian J. Wietecha-Reiman, Todd A. Palmer
On-Site Speaker (Planned) Ian J. Wietecha-Reiman
Abstract Scope Introduction: Statistical meta-analysis of additively manufactured (AM) 316L austenitic stainless steel and Ti-6Al-4V have revealed the importance of transition between defect and microstructure driven fatigue. Even in cases where the presence of processing defects is mitigated, they can still detrimentally impact fatigue performance. In order to understand the degree to which remaining processing defects are impacting fatigue performance, a tool is required which can provide estimates of fatigue performance based off of non-destructively identified processing defects. Quantitative fractography techniques developed on Ti-6Al-4V have provided the capability to connect specific features of crack initiating defects to fatigue life in such a way that defects imaged using x-ray computed tomography (XCT) a fatigue life-based ranking of defect severity. This pipeline between quantitative fractography to a large quantity of XCT data acts as a database for statistical survival analysis of new processing defects to be performed. Experimental Procedure: Validation was in part performed using two sets of fatigue specimens. Specimen chemistry, which was measured using direct current plasma emission spectroscopy and inert gas fusion and combustion, was 6.42 wt.% Al, 3.94 wt.% V, 0.18 wt.% Fe, 0.0172 wt.% C, 0.0015 wt.% S, 0.1374 wt.% O, and 0.0223 wt.% N. All material used to fabricate the test specimens was produced using the L-PBF process on a 3D Systems Model ProX 320 system. All specimens had a layer thickness of 60 µm and were printed at 90° to the build plate. Manufacture and testing of specimens in the first two rows of Table 2 is described elsewhere [2]. All other fatigue specimens were scaled down to have a 5.5 mm gauge diameter after machining. Sub-sized specimens were tested on an MTS 810, servohydraulic load frame with a 100 kN axial load cell. Specimens were tested at a load ratio of 0.1 and frequency of 15 Hz at stress maxima of 400 MPa and 780 MPa. Prior to testing, each specimen was analyzed using x-ray computed tomography (XCT) to characterize the presence of process-related and intentional defects. A GE v|tom|x L300 nano/microCT system was used with an accelerating voltage of 220 kV, a beam current of 0.045 mA, source-to-detector distance of 800 mm, and an exposure time of 2,000 ms to produce a voxel size of 10 µm. After testing, the fracture surface of each fatigue specimen was characterized using an Apreo S Scanning Electron Microscope at an accelerating voltage of 2.0 kV, a beam current of 0.1 nA, and a dwell time of 500 ns. Confocal white light interferometry was performed on crack initiating defects to obtain height maps. A numerical aperture of 0.5 was used, as calculated using Sparrow’s criterion. Results and Discussion: Over half a million processing pores were characterized through XCT to create a large database to compare pore characteristics and estimate severity off of. Pores were first assessed in terms of volume. The use of empirical cumulative distribution functions provided a quick means to show how the collection of smaller pores combine into the overall porosity of the material. By calculating the skewness and kurtosis of pore volume distributions, it was found that they follow a strong log-log relationship with each other. Specimens with larger pores tend to have more of those pores. Statistical modeling demonstrated how this trend can be connected back to the choice of processing parameters. Pore morphology was chiefly characterized according to the Zingg shape criterion which classifies morphology as spherical, rod, blade, or disc. Although a wide range of defect morphologies are obtained when comparing flatness and elongation, the majority of defects images were classified as either spheres or rods. While illuminating, such a result is not necessarily actionable. The fractal-topology technique for quantitative fractography was used to evaluate the geometric characteristics of internal and sub-surface initiated fatigue cracks. Through these measurements, a strong quadratic relationship was observed between fisheye area normalized by specimen diameter and fatigue life. Modeling in-vacuum crack growth as an ellipse established the first equation to predict defect severity. Additional details about the defect were incorporated by generating height maps around the defect. Assuming a symmetric fracture surface near initiation, estimates of the radius of curvature were made to include information about defect morphology. Fractographic relationships were applied to the pores characterized through XCT. Linear regression of these metrics provided the metric of defect severity. Kaplan-Meier type survival curves were produced to visualize the probability of a certain type of processing defect initiating failure. When defect severity was scaled by the ratio of tensile strength to applied stress, experimental fatigue lives matched closely with the bend of the knee of the survival curve where fatiguing past this defect severity becomes less probable. A 90% average value can be applied, and tolerance band created by considering plus or minus one standard deviation to develop a range of tolerable fatigue lives. Conclusion: XCT techniques provide a means to image a large population of processing defects. While these defects may be characterized in terms of size, location, or morphology, there still is a lack to connect XCT data to experimentally obtained fatigue lives. Quantitative fractography provides a means to do so. Modeling fatigue crack growth and final ligament length of internal and sub-surface fatigue cracks provided a means of estimating the degree of in-vacuum crack propagation. This metric followed a strong quadratic relationship with fatigue life. Refinements to this metric were obtained by estimating defect radius of curvature from height maps. Both of these metrics are readily transferable into a set of equations that when applied on XCT data yield a ranking of defect severity. Subsequent survival statistics provide a means to estimate tolerable fatigue lives given the presence of a defect of certain severity. Keywords: titanium alloys, additive manufacturing, fatigue, defects, x-ray computed tomography
Proceedings Inclusion? Undecided

OTHER PAPERS PLANNED FOR THIS SYMPOSIUM

A Brief History of Welding Metallurgy in IIW
A Fundamental Investigation into Intermetallic Formation and Growth in the Aluminum-Iron System using Resistance-based Diffusion Couples
A New CALPHAD-based Finite Element Tool for Additive Manufacturing Simulation
Accelerating Ni-Cr Filler Metal Design with a Coupled CALPHAD and Data Analytics Approach
Additive Manufacturing and Welding of Ni-base Superalloys for Concentrated Solar Power Systems
Additive Manufacturing of Steel-aluminum Bimetallic Structures
Alloy Design and Additive Manufacturing of Functionally Graded Materials for Olefin Furnaces
Alloy Development via Multi-wire Arc Additive Manufacturing (m-WAAM)
Application of NDE Techniques for Safer Pressure Vessels
Applications of Emerging Artificial Intelligence Tools in Additive Manufacturing
Arc and Droplet Transfer Behavior During Electrode-negative Polarity Cold Metal Transfer and Electrode-positive Pulse Gas Metal Arc Deposition of Ti-6Al-4V Alloy
Arc Length Behaviour and Voltage Predictions for GMAW-Sp Aluminum Procedures in the Lincoln Procedure Handbook
Automated Vision-based Laser Weld and Braze Quality Systems
Bond Formation Mechanism of High-frequency Electric Resistance Welding Of X65 Grade Pipeline Steel by Physical Simulation
Capacitor Discharge Based Resistance Welding of Aluminum Alloy and Galvanized Steel Sheets
Carbide Precipitation during Temper Bead Welding in the HAZ of Low Alloy Steels
Challenges in Wire-Arc Additive Manufacture of Nickel Aluminum Bronze
Characterization of Vibration Welded Wood
Charpy Reconstitution Joining Procedure: Supporting Reactor Pressure Vessel Operation Beyond 60 Years
Comparison of Constant Load and Slow Strain Rate Tensile Tests for Evaluation of Hydrogen Assisted Cracking Susceptibility in Dissimilar Metal Weld
Comparison of Crystallographic Texture Before and After Post-weld Heat Treatment of Electric Resistance Welded X65 Linepipe
Computational Design of Experiment Process-microstructure-property Optimization in Welding and Additive Manufacturing
Computational Process-Microstructure-Property Optimization for Fe-10Ni Groove Welds
Connecting X-ray Computed Tomography to Fatigue Life of Ti-6Al-4V using Quantitative Fractography
Construction of a Unified Fatigue S-N Curve Incorporating the Effects of Residual Stress Level in Welded Joints
Correlation Between the Coarse and Fine Grain Haz Hardness of Pipeline Girth Welds
Creep Performance of Austenitic Stainless Steels Processed with Wire Arc Directed Energy Deposition
Critical Evaluation of NDE Methods and Their Effectiveness for Defect Detection in Laser Powder Bed Fusion Components
Crystallographic Texture and Microstructure of Dissimilar Steel Welds for Filler Metal Selection
Database of Hydrogen Assisted Cracking Susceptibility in Dissimilar Metal Welds
Deep Learning Based Real-time and In-situ Monitoring of Weld Penetration: Where We are and What are Needed Revolutionary Solutions?
Defect Formation Mitigation during Laser Welding of Aluminum Alloys using Beam Oscillation
Deleterious Effects of Laser Welding Nitinol without Argon Shielding Gas
Development of a Fast Analysis Solver for Welding Sequence Optimization of Ship Structures
Development of a New Technique to Assess Spot Welding Cracking of Gen3 High Strength Steel Sheets
Dissimilar Brazing of Ti-6Al-4V to Stainless Steel Under Thermal Conditions used for Glass Sealing
Do We Need a New Foundation to Use Deep Learning to Monitor Weld Penetration?
Droplet Temperature Measurements in GMAW
Effect of Additive Manufacturing Process Parameters on the Microstructure and Mechanical Properties of AF9628 Steel
Effect of Base Metal Dilution on Microstructure and Thermal Stability in Anviloy Wire-H13 Clads
Effect of Martensite-Austenite Morphology on Charpy Toughness of Cold-wire Tandem Submerged-arc Welded X70 Steel
Effect of Preheating Temperatures on Microstructure of L-DED Grade 91
Effect of Retained δ-ferrite on the Nucleation of Laves Phase during Artificial Aging in Grade P92 Steel Welds
Effect of the Notching Method on Charpy V-notch Impact Energy Outcomes
Effect of Wire Preheat and Feed Rate in X80 Steel Laser Welds
Effects of Deposition Sequence on Microstructural Evolution in Additively Manufactured Cu-Cr-Nb Alloy / Superalloy Bimetallic Structures
Energy Distribution and Effects on Weld and Defect Formation during Beam Oscillation Laser Welding of a Nickel Alloy
Erection Stage Longi Welding Robot System in Shipbuilding
Estimation of Bead Size and Catchment Efficiency in Laser Cladding
Evaluation of Inoculated High Strength Aluminum Wire 6061 for GMA DED
Feasibility of LP-DED and L-PBF Processes in the Repair of GTD 111 Turbine Blades using René 65 Powder
Fluidity of Aluminum Welding Wires
Friction Stir Welding of Rolled Homogenous Armor (RHA) and High Hardness Armor (HHA) Steels
From Frustrating to Flawless: Mastering Class A Aluminum Resistance Welding
General Linear Models in Additive Manufacturing: Interpretability and Prediction of Aggregated Ti-6Al-4V Fatigue Data
General Thermomechanical Model of FSW Based on a Characteristic Temperature for Deformation and Heat Transfer
Geometrical Feature Development for Multi-Process DED of Aerospace Structures using Ultra High Strength Steel (UHSS)
High Ductility Brazes of Nickel-superalloys Using a Multi Principal Element Alloy Filler
Hot Wire Semi-auto Gas Tungsten Arc Welding (GTAW) for Shipbuilding Applications
Identifying Deposit Profile for Gas Metal Arc Directed Energy Deposition
Industrialization Challenges in Welding and Large Scale Metal Fabrication
Influence of Alloy Composition and Nitride Formation on Delta Phase Precipitation in Additively Manufactured Inconel® 625
Influence of Hydrogen Shielding Gas Additions on Base Metal Dilution, Bead Shape and Wall Buildability in Fe-10Ni Gas Metal Arc DED
Influence of Welding Parameters on Weld Reinforcement in Tandem Submerged Arc Welding
Inoculated High Strength High Strength Aluminum Wire Feedstocks for Welding and DED
Integrating a Novel Approach to Advanced Materials during Resistance Spot Welding for the Automotive Industry
Investigation of Defects Process Map in Friction Stir Welding
Investigation of Fe-10 wt.% Ni Steel Weld Metal Hydrogen Induced Cracking Susceptibility using the Gapped Bead on Plate (GBOP) Test
Investigation of Intermetallic Phase Formation during RSW of Advanced Automotive Steels and Aluminum Alloys
Isothermal Low Cycle Fatigue of Steel to Ni-based Alloys Dissimilar Joints
Laser Beam Directed Energy Deposition (L-DED) of an Fe-Si-B-Nb-Cu Soft Magnetic Alloy
Laser Beam Welding of Wrought and Additively Manufactured Ti-5Al-5V-5Mo-3Cr Alloys
Laser Welding of Al-Cu Interconnects for E-Mobility Applications: Effect of Beam Oscillation on Metal Mixing, Microstructure, and Mechanical Property
Linear Solid State Welding w/ NO Fusion Line. Fine Grained Base to Base Using 95% Less Energy
Machine Learning for GMAW Weld Quality
Machine Learning for Predicting Weld Quality and Properties in Resistance Spot Welding Process
Mapping of a Resistance Spot Weld Properties onto a Space Defined by Base Material Attributes
Mechanizing Self Shielded Flux Core Wire to Achieve Robust Toughness on Girth Welds in Pipeline Construction
Metallurgical Characterization of Rotary Inertia Friction Welded Dissimilar 422 Martensitic Stainless Steel to 4140 Low Alloy Steel Piston Joints
Methodology Development of Ultra-high Temperature Mechanical Performance of Additively Manufactured Refractory Alloys
Microstructural Heterogeneities in Electron Beam Additively Manufactured Haynes 282
Monitoring Torch Position and Weld Quality with Reversed Electrode Image during GTAW Process
Monitoring Weld Penetration using a Deep Learning Model Pre-trained from Filtered Current
My 40 Years as a Welding Engineer in the Oil and Gas Industry
Next Generation Double Electrode GMAW Processes for Precision Fillet Welding
Nickel Aluminum Bronze Weld Metal Microstructures in Wire Arc Additive Manufacturing with Cryogenic Cooling
Nondestructive Characterization of Grade 92 Steel Weld Microstructures using, Micro-resolution Ultrasonic Imaging System.
Numerical Modeling of Arc Plasma and Shielding Gas Flows in Wire Arc Additive Manufacturing of Tall Walls
Numerical Modeling of Resistance Spot Welding Processes and Liquid Metal Embrittlement Cracking
Numerical Modelling of Temperature and Velocity of WC-Co-Cr Particles in the HVOF Process using DJ2700 Gun and Hydrogen as a Fuel
Online Quality Monitoring Method in Gas Metal Arc Welding Based on Vision Camera and Laser Vision Sensor
Open-source Numerical Modeling of Solidification Cracking Susceptibility: Application to Refractory Alloy Systems
Optimization and Characterization of FSpJ for Al Alloys and Polymeric Materials: Experimental and Numerical Investigations
OSU Faculty Overview-Metallurgy and Weldability
OSU Faculty Overview-Processes
OSU Faculty Overview - Design, Modeling and Nondestructive Evaluation
Overview of Arc Welding Activities at IIW and Standardization of Laser Welding/Cutting
Overview of RW Projects for the Automotive Industry
Plenary Talk: Delta Ferrite and Rapidly Solidified Microstructure in Welding and Additive Manufacturing of Martensitic Steels
Practical Calculation of Cooling Rate, HAZ Width, and Thermal Features in Welding and Additive Manufacturing
Precipitation Kinetics in Additively Manufactured Alloy K-500 and Commission IV Activities
Predicting Laser Weld Variability in 304 Stainless Steel Resulting from Composition Variation
Process Advantages of Laser Hybrid Welding of Thick-walled Steel Structures of Wind Tower
Process Control of a Custom Designed Adaptive Weld Head
Reduction of Cold Cracking in Welded Overlays via Reduced Martensite Start Temperature
Robotic Path Planning for Wire Arc Additive Applications of Aerospace Aluminum Alloys
Robotizing Double-electrode GMAW by Learning from Human Welders
Scanning for Metrology in Wire-Arc Additive Manufacturing
Shoring Up Long Lead Time Supply Chain Issues of Forgings and Castings using Advanced Manufacturing
SiC and Nickel-base Superalloy Dissimilar Joining using Multi-principal Element Alloy Fillers
Silicate-free Tandem GMAW for Shipbuilding Applications
Solidification Behavior and Microstructure Evolution in Dissimilar Electron Beam Welds between Commercially Pure Iron and Nickel
Solidification Behavior of Laser-wire Directed Energy Deposition Austenitic Stainless Steel
Stress Relaxation Cracking Susceptibility in 347H SS Welds and Their Repairs
The Ohio State University Welding Engineering Program - the First 75 Years
The Role of Diffusion Brazing Technology for the Repair of Gas Turbine Engine Components
The Role of Material Selection and Thermal Cycling on Tool Life in Refill Friction Stir Spot Welding
Thermal Faceting on the Ductility-Dip Cracking Fracture Surfaces of Nickel-Based Alloys – Occurrence, Characterization, and Implications for the Cracking Mechanism
Thermo-Mechanical Fatigue of Welding Defect-containing Boiler Water Walls
Thermodynamic and Kinetic Calculation of Stainless-steel Solidification – revisiting the WRC-1992 Diagram
Ultrasonic Assisted Soldering of Metallized Polymer Current Collectors for Li-Ion Batteries
Ultrasonic Welding of Dissimilar Materials
Ultrasonically Assisted Resistance Spot Welding of Multilayer Foils in Battery Manufacturing
WE in the Power Generation Industry
Weld Vac – A Quiet, Clean Metal Removal System
Welding Engineering in the Aircraft Engine Industry
Welding in Space: Past, Present, and Future
Wobble Laser Beam Welding in Keyhole Mode

Questions about ProgramMaster? Contact programming@programmaster.org