本发明公开一种用于制造表面粗糙度Ra≤5 μm的双相不锈钢热轧中板的方法，其中，包括： 执行铸坯修磨工艺优化步骤，其中，以粗磨结合精磨的方式，使铸坯表面粗糙度Ra≤70μm；执行中板热处理步骤，其中，铸坯加热→初次高压水除鳞→粗轧→二次高压水除鳞→精轧，并且，在 精轧过程中，精轧机的工作辊每个周期过钢量小 于100t，从而获得轧制后钢板；在执行中板热处理步骤后，执行表面抛丸机械除磷步骤，其中，选用合适的钢丸和钢砂的混合丸料，以预定抛丸速度对钢板进行抛丸处理，从而制得期望的热轧中板。本发明制造出的双相不锈钢热轧中板表面粗糙度Ra≤5μm、酸洗色泽均一、及修磨点少，可适用于制造化学品船用双相不锈钢热轧中板。 

The present invention discloses a method for manufacturing a duplex stainless steel hot-rolled medium plate with a surface roughness Ra≤5 μm, which includes: performing a casting billet grinding process optimization step, wherein, rough grinding is combined with fine grinding, Make the surface roughness of the cast slab Ra≤70μm; perform the heat treatment step of the medium plate, in which the cast slab is heated → first high-pressure water descaling → rough rolling → secondary high-pressure water descaling → finishing rolling. The work roll of the rolling mill has a steel volume of less than 100t per cycle, so as to obtain the rolled steel plate; after the heat treatment step of the medium plate, the surface shot blasting mechanical dephosphorization step is performed, in which a suitable mixed shot of steel shot and steel grit is selected The steel plate is shot blasted at a predetermined shot blasting speed to obtain the desired hot-rolled medium plate. The hot-rolled duplex stainless steel plate produced by the invention has a surface roughness Ra≤5μm, uniform pickling color and few grinding points, and can be suitable for manufacturing the duplex stainless steel hot-rolled intermediate plate for chemical ships.