Attention NAE Members
Starting June 30, 2023, login credentials have changed for improved security. For technical assistance, please contact us at 866-291-3932 or helpdesk@nas.edu. For all other inquiries, please contact our Membership Office at 202-334-2198 or NAEMember@nae.edu.
Click here to login if you're an NAE Member
Recover Your Account Information
This is the 27th volume of Memorial Tributes compiled by the National Academy of Engineering as a personal remembrance of the lives and outstanding achievements of its members and international members. These volumes are intended to stand as an enduring record of the many contributions of engineers and engineering to the benefit of humankind. In most cases, the authors of the tributes are contemporaries or colleagues who had personal knowledge of the interests and the engineering accomplishments of the deceased. Through its members and international members, the Academy carries ...
This is the 27th volume of Memorial Tributes compiled by the National Academy of Engineering as a personal remembrance of the lives and outstanding achievements of its members and international members. These volumes are intended to stand as an enduring record of the many contributions of engineers and engineering to the benefit of humankind. In most cases, the authors of the tributes are contemporaries or colleagues who had personal knowledge of the interests and the engineering accomplishments of the deceased. Through its members and international members, the Academy carries out the responsibilities for which it was established in 1964.
Under the charter of the National Academy of Sciences, the National Academy of Engineering was formed as a parallel organization of outstanding engineers. Members are elected on the basis of significant contributions to engineering theory and practice and to the literature of engineering or on the basis of demonstrated unusual accomplishments in the pioneering of new and developing fields of technology. The National Academies share a responsibility to advise the federal government on matters of science and technology. The expertise and credibility that the National Academy of Engineering brings to that task stem directly from the abilities, interests, and achievements of our members and international members, our colleagues and friends, whose special gifts we remember in this book.
Results Found
BY GIGI WANG SUBMITTED BY THE NAE HOME SECRETARY
KUO KING WANG, a pioneer in injection molding of polymers and non-polymer materials that helped the manufacturing industry around the world evolve to its current practices, passed away on Oct. 7, 2022. He used a scientific base for analyzing the injection molding process, integrating and extending existing knowledge across multiple disciplines. By establishing a consortium of global corporations, he expanded the funding of his research. The corporations incorporated the research findings into their manufacturing processes. The relationships continued for decades, and the research results are widely used in manufacturing around the world.
K.K. Wang was born in China in 1922 and grew up in Changzhou. He received his bachelor’s degree in engineering from the National Central University in 1947. His college years were difficult, as the war raged and food was scarce. After obtaining his degree, he moved to Taiwan to work for what became the Taiwan Shipbuilding Company from 1948 to 1960, where he managed the construction of supertanker projects in his late 20s and early 30s. Looking for more opportunity, he came to the United States and landed in Wisconsin, where he pursued a master’s degree at the University of Wisconsin while working for the Walker Manufacturing Company. After receiving his degree, K.K. made the decision to devote all his time to pursuing a doctorate, which he received from the University of Wisconsin-Madison in 1968. He then joined the faculty as an assistant professor in mechanical engineering.
In 1970 K.K. joined Cornell as an associate professor in the Sibley School of Mechanical Engineering to teach courses and conduct research related to manufacturing. Around that time, the Eastman Kodak Company was developing a revolutionary new product, which would be a reusable, low-cost, pocket-sized camera. The camera was mostly plastic, made by injection molding. In trying to set up for mass producing the product at low cost, it was found that the mold could not be fully filled, and the molded parts contained defects. The company used trial and error to troubleshoot but could not find a solution, thus delaying the introduction of the product. Kodak’s CEO at the time, a Cornell alumnus and member of the advisory board for the dean of engineering, asked the dean if it would be possible for academia to help develop a scientific basis for mold design and process control. The message was passed on to the Department of Mechanical Engineering and eventually reached K.K. for consideration. Internal discussions were initiated with colleagues in Chemical Engineering and Material Sciences. The director of industrial liaison in the dean’s office arranged for discussions with Kodak’s technical staff, resulting in the Cornell team submitting a proposal to Kodak. The technical staff at Kodak reviewed and agreed to the proposal, but corporate management ultimately did not sign off, citing concerns over intellectual property rights of the research that would be generated.
This turned out to be fortuitous, as K.K. and the Cornell team submitted a proposal to the National Science Foundation (NSF) instead. In 1970, the United States was facing three challenges: energy, the environment, and productivity. To study these problems, NSF launched an exploratory program called Research Applied for National Needs (RANN) in 1971.1 After it was launched, RANN mostly supported research to address productivity since environmental issues were addressed by the then recently established EPA and energy issues by the soon to be established DOE. At the time, the annual rate of productivity in the U.S. was increasing more slowly than in other countries, including Germany and Japan. Consequently, most of the grants from RANN supported research on production automation, manufacturing processes, and production systems. K.K., together with a senior faculty colleague in mechanical engineering, submitted a proposal to RANN to study injection molding.
Because of his background in industrial automation, RANN invited K.K. to participate in the review of early projects it supported. The reviewers included others from academia and researchers from industry. In the meantime, K.K. and his colleague’s proposal was accepted and the research started on July 1, 1974, with grant #7411490. This was the birth of the Cornell Injection Molding Program (CIMP).2
The RANN grant ran through 1979 with total funding of over $500,000. After that, the NSF continued to support the project through additional grants. Ultimately, a total of 11 NSF grants provided $3.6 million of continuous support for CIMP through 1998. The NSF’s exceptionally long support of CIMP was a result of the broad industrial support it was receiving, and the project was producing results that significantly improved manufacturing processes.
From its inception, CIMP’s goal was to establish a scientific basis for the injection molding process. Injection molding begins with solid plastic particles being heated in the barrel of a machine and mixed by a rotating screw inside the barrel. The homogenous, highly viscous fluid accumulates around the screw. Molten plastic is then rapidly injected into a cooled mold cavity by the screw. In mere seconds, the part is solidified, the mold opened, and the part ejected. The parts are in final finished shape without the need for a secondary step.
The existing knowledge of rheology and non-Newtonian fluid mechanics at the time was not able to predict the process behavior with any accuracy. From the outset, the CIMP research team took existing knowledge and techniques used in thermal sciences and rheology and tested them through a series of specially designed experiments. All theoretical analyses were tested and verified by experimental results. In this research process the CIMP team developed two new instruments to characterize the basic material properties needed for flow analysis. The first one was used to determine the thermal conductivity of polymer melt as a function of temperature (U.S. Patent No. 4,861,167). The second one was used to determine the viscosity of reactive polymers as a function of temperature, shear rate, and pressure (U.S. Patent No. 6,023,962). These instruments, along with companion simulation software, are used in the injection molding industry today.
In keeping with the idea of solving real-world problems, the CIMP Industrial Consortium was established in 1978. The founding members were Kodak, Cincinnati Milacron, General Electric, General Motors, and Xerox. Then in 1980 K.K. gave a seminar at Hokkaido University in Japan. The general manager of the Technology Center of Sony was in the audience and immediately asked K.K. to visit several of Sony’s production locations and also asked to join the consortium. K.K. returned to the U.S. and discussed Sony’s interest in joining with both the NSF and the consortium members, some of whom were competitors to Sony. They unanimously agreed and Sony became the first foreign CIMP Industrial Consortium member. This opened the floodgates and several major corporations from Japan and Taiwan joined as well. The consortium reached its peak in 1986 with 35 member companies.
The CIMP Industrial Consortium continued over time, and many of the companies were members until the consortium ended with K.K.’s official retirement from Cornell in the early 1990s. After that, K.K. continued working for CIMP for over a decade. There were three active projects during that time, all extensions of CIMP’s earlier work. The first was the Net Shape Die Casting of Complex Parts, which was later renamed Rheomolding; the second was the Pressurized Underfill Encapsulation of Flip Chip on Board; and the third was the Integrated Molding System. The first two were supported by two NSF grants and the third was supported by a few consortium members with strong interest in process control.
The Rheomolding process involved die casting of metals parts, and is detailed in U.S. Patent No. 5501266, “Method and apparatus for injection molding semi-solid metals,” granted to the Cornell Research Foundation in March 1996.
The Pressurized Underfill Encapsulation of Flip Chip on Board was developed at a time when the semiconductor industry was focused on migrating its packaging technique to flip chips. The highly dense, fine pins needed to be protected by filling the gaps with polymer encapsulates. The original method for encapsulation was time consuming and costly. CIMP developed a way to inject the encapsulate and cure it in place, thus reducing the total cycle time by almost two orders of magnitude. The details of CIMP’s process are described in U.S. Patent No. 5817545, “Pressurized Underfill Encapsulation of Integrated Circuits,” granted to the Cornell Research Foundation in October 1998.
The research results from CIMP had a lasting impact on industry. CIMP was a pioneer of academic research, collaborating with industry to solve real-world manufacturing problems. It was known then, and is still true now, that manufacturing processes in the real world are hard to analyze and predict based on first principles. This is particularly true for polymeric materials for which the properties during processing are too complex to model. By applying the latest research in non-Newtonian fluid mechanics, heat transfer, and rheology, along with the invention of new instruments for characterizing material properties, CIMP achieved its goal.
To apply the research to manufacturing processes, computer simulation programs were developed as a by-product of the research. These software applications were highly sought after by the CIMP Industrial Consortium members. As the companies started to use the software, it became a burden to the CIMP research team to provide software support. This became an opportunity for one of K.K.’s Ph.D. students to start a company, AC Technologies, that focused on developing commercial-grade software that would transfer and extend the technologies developed by CIMP to industrial applications. Many CIMP members acquired AC Technologies’ software. The initial product was C-FLOW, a mold-filling simulation. That was followed by the C-PACK and C-COOL products, for simulation of the packing and cooling phases of the injection molding process. The company’s materials lab also provided materials property data for various grades of polymers to be injected.
Over time, the product name morphed into C-MOLD. It was the leading product in the field at the time. Eventually the company changed its name to C-MOLD. AC Technology/C-MOLD was one of the earliest spinoff companies from Cornell. C-MOLD was acquired by Moldflow Inc. in 2001. Moldflow was then acquired by Autodesk in 2008.3
Today, C-MOLD software, based on CIMP’s research results, can predict the behavior of the injection molding process accurately and is used in manufacturing throughout the world. The old mold trials that used to take weeks or months can be done in hours or days on a computer with more accurate results. As an example, developing a production mold for a laptop computer casing typically took three to six months. A large plastic part such as a bumper or instrument panel of a car took over six months and could cost millions. With the new simulation tools, these tasks have been reduced to days, or even hours, and a physical mold trial is often not necessary. This is the reason many plastic parts used in consumer electronics like laptops and televisions can be brought to market so quickly and inexpensively.
K.K. received numerous awards and accolades over his long career, most prominently being elected a fellow of the National Academy of Engineering in 1989. Beyond that he had received the Blackall Machine Tool and Gage Award from the American Society of Mechanical Engineers in 1968, Adams Memorial Membership Award of the American Welding Society in 1976, and the first TRW Fellowship in manufacturing engineering in 1977. He was also a fellow of the American Society of Mechanical Engineers, Society of Manufacturing Engineers, and the International Institution for Production Engineering Research.
Outside of work, K.K. was dedicated to his family and actively involved with his three children. He attended school meetings, followed their extracurricular activities, and was always available to help with schoolwork if asked. K.K. and his wife Cindy spoke Chinese with their children at home to be sure the children would be conversant in Chinese.
K.K. and Cindy traveled the world together, having visited every continent except Antarctica. After they both retired, they continued traveling near and far with friends and family. They took some memorable trips to their native China, visiting places they had learned about as school children but had not seen.
In the last two decades of his life, K.K. and Cindy were financial supporters of two universities. In 2001 they established and endowed the Kuo K. and Cindy F. Wang Professorship4 at the University of Wisconsin-Madison, where K.K. received his M.S. and Ph.D. degrees in mechanical engineering.
K.K. was also a significant supporter of the Sibley School of Mechanical and Aerospace Engineering at Cornell University where he endowed the annual K.K. Wang Industry Day event, at which Cornell researchers, global corporations, and startups come together to share ideas. An Upson Hall classroom was also named for him.
He was predeceased by Cindy, his wife of 60 years.
_________________________ 1www.nsf.gov/about/history/timeline70s.jsp 2ecommons.cornell.edu/items/4b28fb8e-6bad-48a4-820e-c6efc3d52b87 3Cornell University. 1997. “Small Business Development, 1996-1997.” Office of the Vice President for Research and Advanced Studies. Ithaca, New York. 4University of Wisconsin Newsletter, spring 2015:6-7.