Get Post slug with a WordPress function

I’m playing with in_category and switch for change the presentation of some post (inside the loop, of course). Some posts will have a image; then, I want to know how can I get the Post Slug with a WordPress default funcion for use it beyond the permalink.

Example:
Post title: Juan Correa
Post slug:juan-correa
Code:

<h1>Post title</h1>
<img src="images/fichas/Post slug">

That’s all