Within a <form> buttons without type defenido behave as type="submit". Then you need to have type="button". 
To make it redirect to another page you can inline like this:
<form name='form' method=post action='link' enctype='multipart/form-data'>
   <button type='submit'>Enviar</button>
   <button type="button" onclick="window.location='http://google.com'">link</button>
</form>
or with an event headphone like this:
var btn = document.querySelector('button[type="button"]');
btn.addEventListener('click', function(){
    window.location='http://google.com';
});
Having in HTML only:
<button type="button">link</button>
							
							
						 
Place a javascript event on the button, which changes the value of
window.hrefto the address you want to go to. Remember this will not cause a post.– Oralista de Sistemas