Don't kid yourself China has some huge problems to get over and inflation in food pricing is a major one. Gets any worse and you could see rioting.
If North America and Europe stop or slow buying you can bet China's use of base metals will drop fast and hard. Buy a power tool and it contains copper, zinc etc., right down the list of all those things made in China cheaply for export and figure 50% of the content is raw material that will not be bought if the items can't be exported.
Honestly China is not immune from N.American financial meltdown and recession will greatly lower demand for raw materials.