The world's biggest fixed-income investors, fed up with yields on benchmark government bonds that pay less than zero percent, say they've found a new haven from turmoil sweeping global markets: corporate debt.

BlackRock Inc., Glenmede Corp. and at least four other firms that collectively manage in excess of $4 trillion are putting more of their money into the bonds of companies, contributing to a record rally. The Bank of America Merrill Lynch Global Broad Market Corporate Index, which tracks 9,542 debentures, is on pace to gain 3.61 percent in July, the most since being created in 1997, and 14 percent for the year including reinvested interest.

"You have rates markets like the U.S., the U.K. and Germany which look incredibly expensive," Ewen Cameron-Watt, the chief investment strategist for a unit of New York-based BlackRock, the world's biggest money manager with $3.56 trillion in assets, said in a July 17 conference call from London. The firm favors "stuff that gives you a real yield," he said.