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Forensic Materials Scientist Or “Whodunit” Detective

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Forensic Materials Scientist Or “Whodunit” Detective S-E-A SEAlimited.com FALL 2019 FORENSIC MATERIALS SCIENTIST OR “WHODUNIT” DETECTIVE Being a forensic materials scientist is being a “whodunit” detective, tasked with determining why a product or process allegedly failed and who is responsible. Robert S. Carbonara, Ph.D. Forensic materials science is a broad devices (bolts, etc.), hoses and piping, Why the “so what” question matters technical discipline, that analyzes physical amusement rides, firearms, glassware, To illustrate the importance and practical evidence using the principles of physics and bicycles, CPVC piping, sprinkler systems, application of answering the “so what,” chemistry. Before the advent of modern storage tanks, and numerous others several complex case profiles are presented. engineering materials, most forensic • Material Production and Manufacturing These cases involved: (1) a serious injury materials scientists worked with metals and Processes — Recycling precious metal, where there was responsibility avoidance by were called metallurgists. Today, forensic aluminum and steel furnace operations, the parties involved, (2) a very complex metal materials scientists work with an metal casting operations, metal forging assortment of materials, including plastics, recovery process with a seven-figure loss and rolling production, pipe claim, (3) medical devices that fail and are ceramics, glass, composites, even wood and manufacturing leather and, of course, metals. Despite the complicated by issues of patient or doctor • Construction — Beams and support conduct, and (4) a pipeline failure that oc- broadening of the materials spectrum, the structures, welds, safety device material, same scientific principles that apply to metals curred many years after installation and with lifting cables, chains and straps, hoisting multiple possible technical failure scenarios. also apply to other materials. devices, and cranes A portion of the work done by CASE 1. Trucks and semi-tractor trailers forensic materials scientists deals with the • Health Sciences — Surgical instruments, traveling at highway speeds can, fixation devices, implants, patient care and analysis of material failures. However, forensic in some instances, become lethal objects. hospital equipment. materials scientists also investigate the A wheel, weighing hundreds of pounds, production of materials, including raw During any investigation, it is important that comes off a semi-tractor trailer can material and fabrication processes. to assess the available information and continue down the road close to the speed evidence to identify if there are missing of the trailer. An oncoming vehicle, also at Materials impact everything pieces of either or both. One of the major highway speed, will be approaching the challenges in complex cases is to eliminate loose wheel with combined speeds of up to Materials scientists investigate issues the extraneous information and evidence and over 100 miles per hour. Due to regarding: and focus on the “so what” question. the small profile of the wheel, the • Transportation — Components used The forensic materials scientist not only ability of the oncoming driver to in trucking, automotive, rail, marine determines if it corroded, fatigued, or adjust course is minimal, especially if the and aero vehicles, oil and gas pipelines was overloaded, etc., but also must wheel is bouncing, as it often is. This • Consumer and Industrial Products — assess the methodology and results for logical is an extremely dangerous situation, often Valves and fittings, appliances, fastening consistency with the known facts. resulting in serious injury and/or death. S-E-A SEAlimited.com FALL 2019 This wheel-off case involves a CASE 3. Materials scientists investigate records for steel-making processes in the semi-trailer that was found to have the failure of medical devices, e.g., ortho- late 1800’s and early 1900’s, it was possible a fractured axel that had a weld pedic fixation devices, implants, pacemak- to establish that the pipe was made and repair. Welding is not a permissible ers, surgical instruments and patient care installed in 1895, while the sewer manhole repair to an axle, so none of the several- apparatuses. A device may fail because a was installed in 1921. The manhole surround- involved parties would admit to making patient did not follow their doctor’s ing the pipe allowed moisture from the the repair. Using a scanning electron orders, due to doctor error, or for a number water running through the sewer to cause microscope (SEM) with energy dispersive of other reasons. the pipe to corrode and fail at the manhole spectroscopy (EDS), a concentration of a Following spinal fixation device surgery, location. Even though it was over 100 years specific element was found in the weld the patient’s pain was significantly mitigated, old, when examined by S-E-A, the remain- slag. This element is only present in a and he decided to go bowling. This der of the pipe was in remarkedly good certain class of welding rods. S-E-A asked activity caused him to break several pedicle condition with very little corrosion. This is for a discovery request for the welding rod screws, which he claimed were defective. The not unusual since there is very little active purchase orders of the potential welder(s). investigation revealed the screws failed by oxygen underground, if water is not present. The purchase order records were the most fatigue and there were no material defects in Forensic materials scientists deal with reliable way to establish which welding rod them. The fatigue was the result of the loads issues where someone’s (personal or each company used. Once the purchase being put on the screws before they were corporate) actions have resulted in a loss. orders for welding rods from each of the fully incorporated in the bone structure. Using the scientific method and knowledge involved parties were reviewed, the one Bowling shortly after having back surgery is of the materials involved, the forensic purchaser of that class of welding rods was not recommended! materials scientists will establish a basis for identified and the identity of the welder was In some cases, device failures are the establishing “whodunit.” revealed. result of doctor error. For example, during CASE 2. A large international chemical laparoscopic spinal surgery an instrument company was recycling product that was grossly mishandled, due to the doctor’s contained precious metals. After scaling up frustration, causing it to separate and the induction smelting furnace it used for leaving a portion of the instrument in the recovering the precious metal, the company patient and requiring additional surgery. realized a sudden shortfall in its accounting When the device was examined, the of the precious metal output. The company’s separation was determined to be the result insurance policy had coverage for any of an overload force administered by the loss of precious metals. If the company surgeon “exuberantly pulling” on it. In Author Robert S. Carbonara, Ph.D, is a could show a physical loss, perhaps by Materials Scientist / Metallurgist who has been another instance, pedicle screws caps were theft, the insurer had to pay. The dollar performing materials forensic analysis for amount of the loss was in the not properly tightened by the surgeon, 40 years. He has been with S-E-A for 31 years. seven-figure range. The insurer requested which allowed the fixation to come un- Dr. Carbonara received his Bachelor of Science S-E-A to investigate if there was a physical done, again requiring additional surgery. degree in Physics from the University of loss of precious metals. Microscopic examination of the two rods Pittsburgh, and his Doctor of Philosophy degree in The recovery process had numerous used for the fixation showed the Materials Science from the University of Cincinnati. steps and complex relationships between marks from the contact of the caps on the steps. The investigation showed that one rod was significantly different from He did Graduate Studies in Physics at the when some steps in the process were the other, indicating a different amount of University of Pittsburgh and Graduate Studies in Metallurgy at Carnegie-Mellon University. scaled up, the relationships between the contact force on each one, due to a difference steps did not scale in a linear fashion. in tightening. There were no design or Dr. Carbonara is responsible for performing When all the processes were analyzed, it manufacturing defects in any of the and supervising the testing and evaluation of was found that the scaled-up smelting devices used in these instances. samples, as well as analyzing the results. Areas of process did not directly measure the smelting activity include forensic analysis of metals, glass, furnace dross or slag, which still had CASE 4. Why do pipelines fail? Some ceramic, and polymeric materials, and general residual precious metal content. Two pipelines have failed due to improper failure analysis. assumptions were made by the chemical backfill, some have failed (even years later) He has provided testimony in state and federal company: (1) that the concentration of after being hit by excavating equipment courts of law and in the Canadian federal court. precious metal in the old process slag and some fail from corrosion. The long- held for the new scaled-up process, and term failures are usually complicated by (2) it was unnecessary and/or inconvenient issues of who did what and when. One case to measure the amount of dross or involved a dispute regarding a very old slag produced by the new scaled-up (+100 years) gas line that was surrounded furnace. S-E-A showed these assumptions by a sewer manhole. At issue was, which were erroneous and the company did came first, the pipeline or the manhole? not have a physical loss of precious Was the manhole put around the pipe or was metals. Instead, the metals were in the the pipe run through an existing manhole? slag. This analysis saved the insurance By analyzing the steel pipe composition and Know.
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