LUXEMBOURG ( TheStreet) -- ArcelorMittal ( MT), the world's top steelmaker, swung to net profit of $1.7 billion in the second quarter from a year-earlier loss of $792 million. Sales were $21.7 billion, an increase of 43% from the second quarter of 2009. "The improved performance in the second quarter is in line with our expectations and reflects the continued slow and progressive recovery," said Lakshmi Mittal, chairman and CEO, in a statement Wednesday. It's the fourth consecutive quarterly profit for the steelmaker. But the CEO did issue a note of caution saying although the "third quarter will be impacted by a combination of seasonal factors and the effects of the economic slowdown in China, underlying demand continues to show improvement. The challenge for the second half of the year will be to pass on the full extent of cost increases to our customers." The company said earnings before interest, taxes, depreciation and amortization for the third quarter would come in between $2.1 billion and $2.5 billion, below analysts' forecasts. ArcelorMittal said it also is evaluating spinning off its stainless division. -- Reported by Joseph Woelfel in New York. Get more stock ideas and investing advice on our sister site, Stockpickr.com.