Reaction-sintered silicon carbide tubes contain free silicon, which significantly reduces their corrosion resistance in certain environments. As shown in the table, pressureless sintered silicon carbide tubes exhibit significantly better corrosion resistance than reaction-sintered silicon carbide tubes in concentrated sulfuric acid, hydrofluoric acid (HF), and strong alkaline solutions (NaOH, KOH). Extensive industrial practices both domestically and internationally have confirmed that pressureless sintered silicon carbide heat exchangers have more pronounced advantages over reaction-sintered silicon carbide heat exchangers in terms of energy efficiency and service life.