ajax does not load the image or audio type file

hi that such good afternoon I have a doubt does not load the image or audio file type when I give send my modal window nothing saves me the name Mixe and Spanish name and does not save the image or audio ... thanks

this is my code js and my form

                                <form class="form-horizontal" method="get" id="form1"
                                    action="${actionUrl}" modelAttribute="palabra" role="form">
                                    <div style="width: 60%;">

                                        <div class="form-group">
                                            <label for="imagen" class="col-lg-2 control-label">Imagen:</label>
                                            <div class="col-lg-10">
                                                <input type="file" class="form-control" name="imagen"
                                                    id="imagen" placeholder="imagen">
                                            </div>
                                        </div>
                                        <div class="form-group">
                                            <label for="nombreMixe" class="col-lg-2 control-label">Palabra
                                                Mixe:</label>
                                            <div class="col-lg-10">
                                                <input type="text" class="form-control" name="nombreMixe"
                                                    id="nombreMixe" placeholder="nombreMixe">
                                            </div>
                                        </div>
                                        <div class="form-group">
                                            <label for="nombreEspanol" class="col-lg-2 control-label">Palabra
                                                Español:</label>
                                            <div class="col-lg-10">
                                                <input type="text" class="form-control"
                                                    name="nombreEspanol" id="nombreEspanol"
                                                    placeholder="nombreEspanol">
                                            </div>
                                        </div>
                                        <div class="form-group">
                                            <label for="audio" class="col-lg-2 control-label">Audio:</label>
                                            <div class="col-lg-10">
                                                <input type="file" class="form-control" name="audio"
                                                    id="audio" placeholder="audio">
                                            </div>
                                        </div>
                                        <div class="float-right">
                                            <input type="button" class="btn btn-default"
                                                data-dismiss="modal" value="Cerrar" />

                                            <input type="submit" class="btn btn-primary"  id="enviar" 
                                                value="Enviar" />
                                        </div>
                                         <div id="respuesta"><!-- Respuesta AJAX --></div>
                                    </div>  
                                </form>

    $ (document) .ready (function () {
         $ (document) .on ('submit', '# form1', function () { var data = $ (this) .serialize ();

$.ajax({
    type:'GET',
    url: 'agregarPalabras',
        data:data,
    modal: true,
    title: 'Palabras',
    beforeSend:function(){  
 $('#respuesta').html("Insertando datos...");
 },
    success:function(response){
        $('#respuesta').html(data).fadeIn();

// window.location.reload ();             alert ('Successful Changes');         }
    });     return false; }); }); '