Expert Details

Expert in Materials Engineering, Polymers, Metallurgy, Chemistry, Corrosion, and Adhesion Science

Expert ID: 736551 Colorado, USA

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Expertise in chemistry, materials science, metals, polymers, corrosion, coatings and packaging.

Expert has over 20 years of experience working as a technical consultant in materials engineering, polymers, metallurgy, chemistry, corrosion and adhesion science. She has been an advisor to companies ranging from start-ups to major corporations and has consulted on issues related to product liability, failure analysis, innovation and intellectual property. She has provided technical consulting services to companies on medical devices, consumer electronics, pressure vessels and piping, recreational equipment, appliances, food packaging and automotive equipment. She is very skilled in interacting with a wide variety of regulatory agencies, attorneys, engineers, investors, researchers and business leaders.

She is experienced in major aspects of product development, including materials selection, formulation, and end-use testing. She has been an expert witness for litigation cases involving polymers, ferrous metallurgy, corrosion and glass. Expert has taught several courses for The American Society for Materials (ASM International) on polymers and failure analysis for medical devices and has been a Visiting Lecturer at the Colorado School of Mines.

Expert also innovates for large companies and assists clients with matters related to intellectual property, including support related to patent filings, submission of invention disclosures, technical due diligence, and technical aspects of trade secret, patent infringement, and patent validity disputes.

Expert has over 35 issued U.S. patents in the areas of advanced coatings and membranes, chemical sensors, flexible electronic barriers, biosensors and chemical and materials processing.


Example Projects:
Medical Device
Passivation study of 416 medical device
On behalf of a medical device manufacturer, the 416 medical device passivation process was analyzed. Passivation of 416 machined parts resulted in surface corrosion from one vendor. An analysis of three other vendors using the A-A-A passivation process followed by humidity testing showed pitting corrosion
and water spots in samples from two of the four vendors. Surface analysis revealed high levels of sodium, chloride and potassium ions. Recommendation to two vendors was to use deionized rinse water, and to use an alkaline soak following the nitric acid bath in the passivation process.

Analysis of RF-welded femoral cannula
Femoral cannula fabricated by welding LDPE tip and HDPE/LDPE extruded tube failed at unacceptable loads during pull testing. Oxidative susceptibility testing (induction time) and fractography results are consistent with excessive heat exposure during welding. Recommendation is made to limit the 200°C heat step to less than 10 seconds.

Degradation study of ENT implant
In support of the 510(k) process, conducted an in vivo and in vitro degradation study of a bioresorbable implant for nasal soft tissue and cartilage reconstruction. Laboratory measurements included intrinsic viscosity and flexural rigidity over time. Report of analysis of test results and comparison to predicate devices submitted to FDA. Device obtained 510(k) clearance without issue.

Failure analysis of adhesive-bonded arterial cannula
An arterial cannula is fabricated by adhesively bonding a polycarbonate tip to a polyurethane cannula. Pull-tests revealed unacceptable break strengths at the bond location. Laboratory examination included bond interface evaluation; surface roughness, energy and tension measurements; contact angle measurements. Light microscopy and contact angle measurements show an excellent bond to the polycarbonate surface but extensive de-bonding at the polyurethane-adhesive interface. Surface wettability measurements on the polyurethane are favorable for bonding but show variability, suggesting contamination. Recommendations are to test surface preparation techniques including a new surface pretreatment and test a shrink-wrap film used during preparation for extractables.

Bioresorbable film evaluation
The effect of polymer degradation and aging on mechanical properties following sterilization and storage was evaluated for a bioresorbable polymeric film. Crystallinity increased and molecular weight decreased following sterilization.

Wireless continuous temperature sensor
In support of the 510(k) submission for wireless sensors, selected suitable mechanical tests for wireless ovulation sensor. Prepared memo-to-file for FDA that outlined comparisons with commercialized (predicate) devices.

Pipelines and Pressure Vessels
Underground Sprinkler Pipe
Testifying expert for leaky underground fire sprinkler system resulting in 1M warehouse damages. Fire protection system constructed using cement-lined ductile iron pipe and cast-iron flanges. Leak occurred initially at joint location because of fractured flange, limiting liability to pipe manufacturer.

Cast-iron ammonia valve
Project manager for metallurgical analysis, litigation strategy and Rule 26 report involving cast iron ammonia valve that ruptured and caused one fatality. Chemical analysis of crack surface showed that the crack valve had been painted over during maintenance work, releasing the valve manufacturer from liability.

Above ground sprinkler pipe
Performed failure analysis of a fire protection system that leaked, causing more than $1M damage. Cause of the failure was found to be improper installation, causing corrosion to occur in the weld seam.

Sierra-Nevada Pipeline Leak
Analyzed a pipeline leak in the Sierra-Nevada mountain range that occurred due to damage from improper installation 50 years prior to the leak. Local damage resulted in increased stresses that initiated slow-growing “near-neutral” stress-corrosion cracking.

High pH SCC rupture
Evaluated the cause of a gasoline pipeline rupture that occurred in a high-population area in Arizona. The cause of the rupture was high-pH stress-corrosion cracking (SCC). Hydrotesting of adjacent pipeline areas was recommended, which revealed other SCC locations that were close to rupture.

Nevada third party damage
Conducted a failure analysis investigation of a gasoline pipeline that leaked in the desert outside of Las Vegas. This pipeline had suffered a gouge from third-party digging. A fatigue crack initiated from the gouge and eventually grew through wall to cause a leak.

Examples- Other Projects:
Glass and ceramics
Champagne bottles manufactured using soda lime glass treated with Freon 134a resulted in excessive blooming on glass, an unacceptable appearance to consumers. Conducted chemical analysis and prepared export report for litigation. A change in Freon type altered surface treatment, limiting effectiveness.

Food Packaging for Produce
On behalf of a food industry group, developed several technical solutions to two problems: extending post-harvest produce quality during long transport times, and increasing value to Asian customers. Technical solutions resulted in three patent applications.

Flexible Electronics
On behalf of an electronic industry group, developed several technical solutions to solve the problem of creating flexible, transparent barrier/substrate materials that can withstand temperatures reached during electronics processing and assembly. Technical solutions resulted in two patent applications for barrier/substrates for flexible electronics.

Microwave Appliance
Examined cracked microwave doors for major appliance manufacturer. After a review of processing conditions found that recent changes in polycarbonate melt flow index resulted in increased susceptibility to ESCR from household oils. Recommended restoring the original melt flow index.

Education

Year Degree Subject Institution
Year: 2003 Degree: M.S. Subject: Metallurgical and Materials Engineering Institution: Colorado School of Mines
Year: 1994 Degree: Ph.D. Subject: Inorganic Chemistry Institution: Yale University
Year: 1988 Degree: B.S. Subject: Chemistry Institution: University of California, Berkeley

Work History

Years Employer Title Department Responsibilities
Years: 2007 to Present Employer: Undisclosed Title: President Department: Responsibilities:
Years: 2002 to 2007 Employer: Exponent Failure Analysis Associates Title: Senior Engineer Department: Responsibilities:
Years: 1998 to 2002 Employer: Exponent Enviromental Title: Senior Scientist Department: Responsibilities:
Years: 1995 to 1998 Employer: Exponent Enviromental Title: Scientist Department: Responsibilities:

Career Accomplishments

Publications and Patents Summary
Publications: 5
Patents: 35
Presentations: 4

Fields of Expertise

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