I could not find the source that I read. It was a youtube video. Anyway, I searched around and here is something I collected.
The US's peak steal possesion per person was 8.8t, UK 7.6t，Japan 10.5t，South Korea 9.5t. China in 2020 is 6.9t if I remember correctly. It is projected that China will reach 10t by 2028 according to the current production trend.
This figure is for domestic usage only. It means all future consumption for China can be recycled through this saving (about 10t per person).
To remain "world factory", China certainly should not use the 10t for exporting cars, ships and rail tracks. It has to come from imported steel or scrap steel or iron ore. I don't have data but Reuters reported in 2011 that China produced 690 million tonnes of steal, of which 40 million exported. Of course, the ships and cars that China exported were not counted in the 40 million. But it seems that the amount used for export is one tenth of China's production. So it seems that after China has enough savings, the required import for being world factory won't be much an issue any way. The import includes "粗钢" (raw steel) and scrapped steel besides iron ore. The raw steel production capacity isn't something China want to keep because of its low profit. The scrapped steel isn't poisonous and polluting garbage like China used to import. Many companies in the west and SK actually bid to buy them.
What happened in the past two decades is that China drastically increased iron ore import for domestic consumption and savings, not for making machines for export. Once China has enough savings, the iron ore import is going to drop drastically. That date is around 2028.
Now back to my original post about iron ore and Australia. For sustaining China's manufacturing competence, keep importing large quantity of iron ore isn't necessary. The small volume needed can be covered without Australia.
