1. The phase transformation and weight loss rate of ludwigite in oxidizing roasting were studied by DTA-TG, isothermal TG and XRD.

2. Boroncontaining pig iron got from ludwigite ore in the eastern area of Liaoning province by blast furnace separation was proposed as raw material to directly smelt boron steel.

3. Results show that it is rather difficult to extract boron from ludwigite if roasting direct the ludwigite and then leaching.

4. Main characteristics and some achievements in comprehensive utilization of ludwigite ore are described.

5. And in the end, the paper proposed that it is urgent necessary to exploiting and utilizing ludwigite resources.

6. Thermodynamic analysis was made to study the reduction volatilization of boron in ludwigite by using carbothermic reduction. Predominance diagram for the BCO system was presented.

7. Main characteristics and part of earlier stage achievements in technological process of comprehensive utilization of ludwigite ore are reported.

8. Experimental results showed that the structure, porosity and particle size of ludwigite ores have a significant effect on the reduction rate.

9. It cost saving, simple and convenient and the result is prone to explain by ludwigite -magnetite prospecting with this method.