Density and hardness pressureless sintered and post-HIPed B4C

A method of preparing a boron carbide article comprising:

• forming a boron carbide compact from undoped boron carbide particles coated by boron oxide;
• forming a boron carbide green body from said boron carbide compact;
• driving said boron oxide out of said boron carbide green body to obtain a reduced boron carbide green body;
• and
• pressureless sintering said reduced boron carbide body at a pressureless soaking temperature that does not exceed 2336° C. to obtain a pressureless sintered boron carbide body.