In general, it is not safe to put metal in a microwave, including a convection microwave. Metal can cause sparks and potentially damage the appliance or even start a fire. However, some convection microwaves come with special metal racks or trays that are specifically designed for safe use in the convection mode.
If your convection microwave has a metal rack or tray provided by the manufacturer, it is safe to use them according to the appliance's instructions. These racks or trays are designed to allow proper airflow and heat distribution during convection cooking. Be sure to follow the guidelines provided by the manufacturer to ensure safe usage.
It's worth noting that even in convection microwaves with metal racks or trays, you should avoid using any other metal objects, such as aluminum foil or metal utensils, as they can still cause sparks or damage the appliance. Always refer to the user manual or guidelines provided by the manufacturer for specific information about using metal in your convection microwave.