NEW YORK (TheStreet) -- Alcoa (AA) - Get Report reported second-quarter earnings missed Wall Street estimates but beat on revenue.

The aluminum production giant has been working to restructure its business following the slump in aluminum prices. After the close Wednesday the company posted earnings of 19 cents per share, up from last year's numbers but coming in short of the predicted 22 cents per share. Revenue was higher than expected at $5.90 billion, up from last year's $5.84 billion.

The metal engineering company's stock has taken a beating in 2015, dropping 30% but was up in extended trading hours. Excess aluminum supply from China and economic weakness in Europe have pushed prices down, forcing Alcoa to cut its smelting capacity by around 33% since 2007. The manufacturer permanently closed its primary smelter in Brazil at the end of June and is reducing its aluminum production to 3.4 million tons per year.

For 2015 the company is hoping to make savings of almost $900 million. Alcoa has been diversifying into auto, aerospace and 3-D printing markets to boost profits but is still feeling the pinch of sluggish economic growth and increasing Chinese exports. China now produces around half of the world's aluminum. The stock was further hit by China's stock market tumble which has seen sharp losses over the last few days.

Alcoa said it boosted productivity with a flurry of acquisitions over the past year to prop up its Engineered Products and Solutions sector. New additions have include leading jet engine components maker Firth Rixon and Tital, a Germany company that produces Titanium structural castings for the aerospace sector.

Alcoa said it expects to see demand increase 6.5% in the aluminum market this year, despite pricing headwinds.