David, who has won four World Open titles in the past five years, needed only 27 minutes to ease past her 20-year-old compatriot on the all-glass court at the Red Sea resort of Sharm El Sheikh.

"It feels good, it's always harder to play a team mate, especially in the quarters of the World Open," David told reporters. "You just have to go out and play your best. I was feeling the ball really early and I feel the best I've ever been."

World number two Jenny Duncalf of England lost to ninth seed Camille Serme 8-11, 11-7, 7-11, 11-2, 11-5 in the tournament's biggest upset.

"I was trying to think about playing point by point and trying not to think about the score," said Serme, who became the first Frenchwoman to reach the World Open semifinals.

Egypt's fourth seed Omneya Abdel Kawy defeated Kasey Brown of Australia 11-8, 14-12, 6-11, 11-5.

Malaysia's David is unbeaten this year and seeking a third successive world title and fifth overall to match the haul of Australia's Sarah Fitz-Gerald.

She will face England's Alison Waters in the semifinals after the third seed's 9-11, 11-4, 11-7, 10-12, 11-8 victory over Vanessa Atkinson of the Netherlands.