Remembered as a humble and effective leader who spent the later years of his life developing sustainable manufacturing processes, UC Berkeley mechanical engineering professor David Dornfeld died last month. He was 66 years old.

Born Aug. 3, 1949, in Horicon, Wisconsin, Dornfeld died of a heart attack March 27. According to his friends and colleagues, he possessed a sincere humility and a warm, jovial disposition that gave little indication of his global recognition as a manufacturing researcher.

“He had a great sense of humor,” said Costas Grigoropoulos, a campus professor of mechanical engineering. “He was warm and always welcoming, but he was also very effective as an administrator.”

Dornfeld began his career at UC Berkeley in 1977 as an assistant professor of mechanical engineering after obtaining his doctorate in mechanical engineering from the University of Wisconsin-Madison. He arrived on campus with a strong background in manufacturing and welding and eventually became chair of the campus’s mechanical engineering department in 2010.

Dornfeld maintained a curious spirit and openly welcomed new ideas, qualities that made him a visionary in his role as the faculty director of the campus’s Jacobs Institute for Design Innovation, according to Jacobs Institute program coordinator Laura Mitchell.

Prior to his work in green manufacturing, Dornfeld was a pioneer in significant manufacturing developments, such as automated welding, according to Roberto Horowitz, chair of the campus’s mechanical engineering department.

Dornfeld was also the director of the campus’s Laboratory for Manufacturing and Sustainability, or LMAS, and ran a popular blog on green manufacturing. He found personal satisfaction in his day-to-day work, said campus senior Amrita Srinivasan, his former student and LMAS undergraduate researcher.

“He was very enthusiastic about everything — very excited to start new projects, meet new people, just explore new ideas,” Srinivasan said. “If you told him you were working on something new, he would light up.”

Colleagues said Dornfeld often expressed care for them. When mechanical engineering professor Tarek Zohdi arrived on campus about 15 years ago, he recalled, Dornfeld immediately welcomed him and invited him out to dinner.

Zohdi remembers Dornfeld as exceptionally down-to-earth and humble, despite his expansive research and position as a global leader in his field. During a drive to UC Davis with Zohdi, Dornfeld took a detour to get onion rings from his favorite spot after Zohdi made an offhand remark about liking onion rings.

“He was a very good citizen of the community,” Zohdi said. “He was truly a humble guy.”

Beyond his research, Dornfeld envisioned designing a more sustainable world, Mitchell said. Dornfeld believed that engineering expertise could be actively applied toward alleviating social problems, she added.

Indicative of his commitment to improving his community, Dornfeld sat on numerous government panels that assessed the ecological and health impacts of manufacturers’ activities and determined whether they were safe for surrounding neighborhoods, according to Zohdi.

An avid reader, Dornfeld was well-rounded in his activities and enjoyed keeping up to date with politics, Horowitz said, adding that Dornfeld and his wife also loved animals and even took to rescuing stray cats.

Dornfeld is survived by his wife, Barbara Dornfeld, and his brother, William.