C. L. Moore

One of my favorite "robot" stories is "No Woman Born," by C. L. Moore:

A famous performer is horribly burnt in a fire; her brain is put into a robotic body.

Her arms were pale shining gold, tapered smoothly, without modeling, and flexible their whole length in diminishing metal bracelets fitting one inside the other clear down to the slim, round wrists. The hands were nore nearly human than any other feature about her, though they, too, were fitted together in delicate, small sections that slid upon one another with the flexibility almost of flesh. The fingers' bases were solider than human, and the fingers themselves tapered to longer tips.

But without her human body, she drifts away from humanity...

"There's so much still untried. My brain's human, and no human brain could leave such possibilities untested. I wonder, though...I do wonder--"

Her voice was soft and familiar in Harris' ears, the voice Deirdre had spoken and sung wiht, sweetly enough to enchant a world. But as preoccupation came over her a certain flatness crept into the sound. When she was not listening to her own voice, it did not keep quite to the pitch of trueness. It sounded as if she spoke in a room of brass, and echoes from the walls resounded in the tones that spoke there.

"I wonder," she repeated, the distant taint of metal already in her voice.