Method for double-sheet thermoforming of a hollow body and resulting hollow body

A twin sheet thermoforming process for manufacturing a hollow body, said process comprising:

• supplying two sheets comprising at least one face consisting of a pseudo-amorphous composition based on polyaryl ether ketone(s);
• a step of softening the two sheets at a softening temperature, so as to form softened sheets,
• the softening temperature being greater than or equal to the glass transition temperature of each pseudo-amorphous composition;
• a step of forming the softened sheets so as to form thermoformed sheets;
• a step of contacting and coalescing at least one contact zone of said faces of the softened sheets, and/or
• of sheets being formed or already formed,
• so as to form an intermediate body, the contact zones being heated to a contacting temperature, each contact zone remaining in an essentially amorphous state at least until contacting;
• and
• a step of crystallizing the composition at a mold temperature, to form a crystallized hollow body,
• the crystallization step being carried out essentially after the contacting and coalescing step.