Record shipments to China helped boost U.S. exports of stainless steel scrap by 16 percent in August.

Shipments to offshore specialty steel mills and scrap traders rose to 108,340 tonnes from 93,265 tonnes in July, according to the latest figures from the U.S. Commerce Department, putting the year-to-date total at 769,096 tonnes, an 8.7-percent increase from 707,621 tonnes in the first eight months of last year.

China emerged as the market leader in August, displacing Taiwan, which had been the top overseas market for U.S. stainless steel scrap for much of the...