Connor Slone

Dr. Slone has applied his expertise to help clients understand and solve problems in many different industries. Selected examples are described below:

Energy and Utilities

• Electric power transmission conductor: failure analyses and proactive bend or shear testing of conductors, including composite core conductors.
• Electric power hardware: Analyses of hot- and cold-end transmission and distribution hardware. These projects have involved failure analyses as well as asset integrity management efforts to evaluate long-term fatigue, corrosion and wear performance of specific components.
• Telecommunications cables: evaluated effects of environmental exposure on metal-clad cables.
• Gasification technology: investigated several aspects of gasification facilities including chloride corrosion pitting in stainless steel process piping and stress corrosion cracking of dissimilar metal injection lance welds.
• Linear actuator springs: analyzed unexpected deformation and failures in nickel-base superalloy springs designed for high temperature applications.
• High-voltage fuses: performed a failure analysis on high-voltage fuses that were igniting under normal electrical loads.
• Solar power components: investigated aspects of components for solar power generation arrays, including cracking in steel torque tube couplers and galvanized coatings for steel components designed to endure 40 years of environmental exposure.

Oil and Gas

• Ongoing transmission integrity management: conducted over a dozen direct cause assessments associated with cutout-for-cause piping components for a large utility operator. Dr. Slone has investigated causes including stress corrosion cracking, selective seam weld corrosion, third party mechanical damage, welding deficiencies, and manufacturing issues, among others.
• In-service leaks and welding burn-throughs: conducted several failure analyses on leaking gas transmission pipelines and welding burn-throughs.
• Crude oil release litigation: supported litigation efforts related to an oil release from a leaking pipeline, which included analyzing in-line inspection (ILI) data.
• Petrochemical facility process piping: supported a multidisciplinary investigation of corrosion in piping at a petrochemical facility, including general corrosion in carbon steel pipes and pitting corrosion in stainless steel pipes. The corrosion was facilitated by delays in the pre-commissioning process for the pipe works, which left standing water in the pipes.
• Subsea pipeline arbitration: assessed documentation relating to a leaking subsea fuel oil pipeline in support of an international arbitration matter.
• Crude oil release: performed a failure analysis following crude oil release from a steel pipe. The direct cause of failure was determined to be internal corrosion.
• Gas pipeline explosion litigation: supported litigation efforts related to a gas pipeline explosion, which was caused by hydrogen embrittlement of hard spots that were produced during pipe manufacturing. Dr. Slone's support included analysis of in-line inspection (ILI) data per API 1163.
• Pressure vessel support weld cracking: investigated the cause of cracking that ran through a stiffener support and the adjacent weld to the body of a pressure vessel. Recommendations were made to the client about evidence preservation because the fractured components were extensively damaged during extraction, resulting in an inconclusive analysis.

Industrial Machinery, Equipment, and Facilities

• Gas turbine investigations: investigated multiple incidents involving fractured compressor blades in gas turbines. The analyses included assessments of non-destructive evaluation techniques and identification of cracking in additional blades. The failure and additional cracks were found to be caused by metal fatigue. 
• Evaporator fan analysis: analyzed cracking in the duplex stainless steel impeller of a zero liquid discharge evaporator fan. Cracking was caused by high concentrations of chlorides that led to stress corrosion cracking.
• Mud drum and steam drum analyses: investigated leaks and cracking in boiler mud drum and steam drum walls caused by stress corrosion cracking.

Buildings and Structures

• Fractured girder investigation: supported failure analysis efforts related to fractures of steel girders. The cracks that led to the fractures were initiated by thermal cutting of the girders.
• Fractured steel bolts: performed a direct-cause failure analysis of bolts used to secure a structural steel moment-resisting frame system. A number of bolts were found to have fractured due to quench cracking and hydrogen-assisted cracking/hydrogen embrittlement.

Consumer Products and Sporting Goods

• Steam cleaners: evaluated the cause of ruptured cast aluminum steam cleaners, which involved a complex interaction between several mechanisms, including internal corrosion of the steam boiler.
• Fractured bicycle components: performed direct cause failure analyses on fractured bicycle spindles, spokes, and frames for multiple companies. Causes of failure have included hydrogen-assisted cracking/hydrogen embrittlement, sub-surface manufacturing flaws, and grain boundary embrittlement due to incipient melting of an aluminum frame.
• Wearable device warping: investigated austenitic stainless steel housings for wearable electronic devices that were warping during the manufacturing process.
• Frying pan rivet caps: analyzed frying pans on which rivet caps were being ejected at high speeds during use.

Vehicles and Personal Transportation

• Utility vehicles: failure analyses of various components in off-road utility vehicles. Examples of components include steering system universal joints and constant velocity joints.
• Motorcycles: failure analyses of various components on internal combustion and electric motorcycles. Examples of components include gasoline tanks and welds. 
• Battery fires: engaged in two multi-disciplinary investigations into vehicle battery fires. Dr. Slone's role was assessing arcing damage and corrosion on metal components around the apparent fire initiation site.
• Drive clutch failures: investigated failures of cast aluminum drive clutches from a brand of off-road vehicles. The failures were related to porosity in the cast components.
• Scooter stem fractures: analyzed fatigue failures of handlebar stems on electric scooters.

Medical Devices

• Orthopedic implant: supported litigation efforts related to the fractured screws on a cervical spine fixation implant.
• Surgical devices: performed several failure analyses related to surgical grippers, clips, and other hardware. Dr. Slone has also engaged in proactive work that involved comparing components of the same design that were manufactured by different processes.

Rindler JJ, Slone CE, Herderick ED, Mills MJ, Ramirez AJ. Investigation on the potential effects of laser stitching and subsequent heat treatment on the microstructure and mechanical properties of nickel alloy 718 produced via laser powder bed fusion (L-PBF). Additive Manufacturing 2022; 57:102906.

Heczko M, Mazanova V, Slone CE, Shih M, George EP, Ghazisaeidi M, Mills MJ. Role of deformation twinning in fatigue of CrCoNi medium-entropy alloy at room temperature. Scripta Materialia 2021; 202:113985.

Slone CE, Barnett B, Georgin B, Vivek A, George EP, Daehn GS, Mills MJ. Solid state welding of medium-entropy CrCoNi with heterogeneous, partially recrystallized microstructures. Materials Science and Engineering: A 2021; 818:141425.

Miao J, Slone CE, Dasari S, Ghazisaeidi M, Banerjee R, George EP, Mills MJ. Ordering effects on deformation substructures and strain hardening behavior of a CrCoNi based medium entropy alloy. Acta Materialia 2021; 210:116829.

Slone CE, LaRosa CR, Zenk CH, George EP, Ghazisaeidi M, Mills MJ. Deactivating deformation twinning in medium entropy CrCoNi with small additions of aluminum and titanium. Scripta Materialia 2020; 178:295 — 300.

Slone CE, George EP, Mills MJ. Elevated temperature microstructure evolution of a medium entropy CrCoNi superalloy containing Al, Ti. Journal of Alloys and Compounds 2020; 817:152777.

Slone CE, Miao J, George EP, Mills MJ. Achieving ultra high strength and ductility in equiatomic CrCoNi with partially recrystallized microstructures. Acta Materialia 2019; 165:496 — 507.

Slone CE, Chakraborty S, Mills MJ, Niezgoda SR. Influence of deformation induced nanoscale twinning FCC — HCP transformation on hardening and texture development in medium entropy CrCoNi alloy. Acta Materialia 2018; 158:38 — 52.

Slone CE, Miao J, Mills MJ. Ultra high strength and ductility from rolling and annealing of a Ni-Cr-Co superalloy. Scripta Materialia 2018; 155:94 — 98.

Miao J, Slone CE, Smith TM, Niu C, Bei H, Ghazisaedi M, Pharr GM, Mills MJ. The evolution of the deformation substructure in a Ni-Co-Cr equiatomic solid solution alloy. Acta Materialia 2017; 132:35 — 48.

Kramb RC, Buskohl PR, Slone CE, Smith ML, Vaia RA. Autonomic composite hydrogels by reactive printing: materials and oscillatory response. Soft Matter 2014; 9:1329 — 1336.

Smith ML, Slone CE, Heitfeld K, Vaia RA. Designed autonomic motion in heterogeneous Belousov — Zhabotinsky (BZ) — gelatin composites by synchronicity. Advanced Functional Materials 2013; 23(22):2835 — 2842.

Smith ML, Heitfeld K, Slone CE, Vaia RA. Autonomic hydrogels through postfunctionalization of gelatin. Chemistry of Materials 2012; 15:3074 — 3080.

Presentations

Slone CE, Miao J, George EP, Mills MJ. Ultra-high strength and anomalous hardening in FCC medium / high entropy alloys. TMS 2018, San Antonio, TX, March 2019.

Slone CE, Miao J, George EP, Mills MJ. Enhanced strength and ductility in Ni-Co-Cr alloys through cold work and annealing. 18th International Conference on the Strength of Materials, Columbus, OH, July 2018.

Slone CE, Chakraborty S, Niezgoda SR, Mills MJ. Experimental and computational analysis of deformation in solid solution and precipitation strengthened Ni-Cr-Co alloys. TMS 2018, Phoenix, AZ, March 2018.

Slone CE, Mills MJ. Elevated temperature tensile and creep behavior of equiatomic NiCrCo. TMS 2018, Phoenix, AZ, March 2018.

Slone CE, Mills MJ. Analysis of strain localization during creep of a polycrystalline superalloy using SEM DIC. TMS 2017, San Diego, CA, February 2017.

Slone CE, Bechetti DH, DuPont JN, Mills MJ. Localized deformation under severe microstructural gradients. National Science Foundation Center for Integrative Materials Joining Science for Energy Applications Meeting, Columbus, OH, January 2017.

Slone CE, Mills MJ. Measurement of strain localization during creep of a polycrystalline superalloy using SEM based digital image correlation. MS&T16, Salt Lake City, UT, October 2016.

Slone CE, Bechetti DH, DuPont JN, Mills MJ. Local measurement of creep deformation in polycrystalline superalloys. TMS 2016, Nashville, TN, February 2016.

Slone CE, Bechetti DH, DuPont JN, Mills MJ. Fundamental understanding of localized deformation under severe microstructural gradients. National Science Foundation Center for Integrative Materials Joining Science for Energy Applications Meeting, Golden, CO, July 2014.

Slone C, Mostaed E, Cline C, Kaplowitz D, Ganot G, James B, Aguiar D. Copper contamination cracking in a pipeline repair weld. Journal of Failure Analysis and Prevention 2024; 24:794 — 804.

Stewart JR, Ganot GS, Slone CE, James BA, Roepke CT. Fractography of weldments. In: Schroeder CJ, Parrington RJ, Maciejewski JO, Lane JF, editors. Fractography. ASM metals handbook, Volume 12; ASM International 2024; 441 — 449.

Slone CE, Kaplowitz DA, Bowers ML, Roepke C, Mazánová V, James BA, Aguiar DJ. Effects of heat treatment on vintage pipeline electric resistance welds. Metall Mater Trans A 2025; 56:3670 — 3680.

• Selected as Best Paper of 2024 in Journal of Failure Analysis and Prevention

Slone CE, Mazanova V, Kumar P, Cook DH, Heczko M, Yu Q, Crossman B, George EP, Mills MJ, Ritchie RO. Partially recrystallized microstructures expand the strength-toughness envelope of CrCoNi medium-entropy alloy. Communication Materials 2024; 5(263).