Can not pass list of object to method by AJAX

Try to put data into formData one by one:

function PayAjax(orders, payment, note) {
        orders = [{ 'id': 1, 'quantity': 2 }, { 'id': 3, 'quantity': 4 }];
        var formData = new FormData();
        for (var i = 0; i < orders.length; i++) {
                formData.append("orders[" + i + "].Id", orders[i].id);
                formData.append("orders[" + i + "].Quantity", orders[i].quantity);
            }
        formData.append('payment', payment);
        formData.append('note', note);

        $.ajax({
            dataType: 'json',
            url: '/sale/pay',
            type: 'POST',
            data: formData,
            processData: false,
            contentType: false,
            success: function (result) {
                var x = 1;
            },
            error: function (error) {
                console.log(error);
            }
        });
    }