Plasma-assisted microwave processing of materials

A microwave heating method, comprising:

• forming a plasma;
• providing an object to be heated within the plasma, the object to be heated formed of a material which is a poor microwave absorber;
• exciting the plasma to heat the object to a predetermined temperature at which the material becomes a better absorber of microwaves;
• extinguishing the plasma once the object has been so heated;
• and
• microwave heating the object once it has reached the predetermined temperature and with the plasma turned off.

A method of heating materials, comprising:

• using microwave energy and a microwave plasma to heat a material in such a way that a center of the material is heated to a higher temperature than a surface of the material;
• heating the center of the material to a point where the center of the material produces a high temperature combustion wave front from the center of the material outward;
• and
• joining the thus heated material with another material.

A microwave processing method, comprising:

• providing at least first and second materials to be processed;
• preheating the first material, and using a microwave to heat the first material until it undergoes an exothermic reaction;
• and
• using the heat from the exothermic reaction to heat the second material.

A method of joining a first material to a second material, comprising:

• forming a plasma in an area of the first material;
• using microwave energy to excite the plasma;
• and
• joining the first material to the second material.

A method of using microwaves and plasma to heat materials, comprising:

• supplying a first material which can form a plasma into an area of a material to be heated;
• exciting said plasma using microwave energy to heat said first material;
• terminating supply of said first material;
• and
• subsequently to said terminating, using microwaves to locally heat the material to be heated.