Jquery ajax load memorystream from MVC controller

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 [Authorize]
        [HttpPost]        
        public FileResult CreateChart()
        {
 chart.ChartAreas.Add(chartArea);
            var ms = new MemoryStream();
            chart.SaveImage(ms);
            GlobalSettings.SessionInfo["HomeChart"] = ms.GetBuffer();
            return File(ms.GetBuffer(), @"image/png"); 
}

<img id="ItemPreview" src="" />

$.ajax({
                       type: "POST",
                       contentType: "image/png",
                       timeout: 10000,
                       url: '@ViewData["BaseUrl"]/Home/CreateChart',

                       success: function (data) {

                               try {
                                   var ImgSrc = data
                                   $('#ItemPreview').attr('src', "data:image/png;base64," + ImgSrc);

                               } catch (error) {
                               }


                       }
                   });