Cara Insert Multiple Input Dengan Ajax dan Laravel

Saya mau tanya cara insert multiple input dengan laravel ajax gimana ya? Ini code ajaxnya :

 $("#update_part_char_value").click(function(e) {
	  e.preventDefault();
	  var characteristic = $("#characteristic").val();
	  // var char_value = [$("#char_value").val()];
	  var char_value = [];
	    $('input[name="char_value[]"]').each( function() {
	        char_value.push(this.value);
	    });

	  $.ajax({
	    type:'POST',
	    data: {material_number: 72001649,characteristic: characteristic,char_value:char_value},
	    url:'{{ url("/workbench/update_part_char_value/") }}/'+72001649,
	    success:function(data) {
	      alert(data);
	    }
	  });
	});

Ini Kode di Controller :

 public function update_part_char_value(Request $request)
    {
        // $characteristic = $request->characteristic;
        $char_value = $request->char_value;
        for($i=0; $i < count([$char_value]); $i++){
            $value = $char_value[$i];

            DB::table('part_characteristic_value')
                ->where('material_number', 72001649)
                ->update([
                    // 'characteristic'   => $request->characteristic,
                    'char_value'   => $value,
                ]);
        }

        return response()->json(['success'=>'Characteristic Value Has Been Updated']);

saya sudah coba kode diatas tapi belum berhasil, mohon pencerahannya.Terimakasih