Various types of sintered metals are used as filter substrates in diesel particulate filters (DPFs), and some are designed to have high sulphur tolerance. However, without specific information or further details, it is difficult to determine the exact type of sintered metal used in the research article you mentioned.

In general, DPFs employ high porosity and filtration efficiency materials to capture and remove particulate matter from diesel engine exhaust gases. Commonly used sintered metals for DPF substrates include silicon carbide (SiC), cordierite, and aluminium titanate.

Silicon carbide (SiC) is a popular choice due to its excellent thermal and chemical stability and high mechanical strength. It can tolerate high temperatures and is resistant to thermal shock. SiC-based DPFs are known for their durability and ability to withstand high soot and ash accumulation levels.

Cordierite is another commonly used material for DPF substrates. It offers good filtration efficiency and thermal shock resistance but may have lower durability than SiC.

Aluminium titanate is a relatively newer material used in DPFs. It offers high thermal shock resistance and a low coefficient of thermal expansion, which can improve the durability of the filter.

It is important to note that the choice of sintered metal for a DPF substrate can depend on various factors, including the application's specific requirements, such as sulfur tolerance in the case of high-sulfur diesel fuel. Different manufacturers and researchers may have their own proprietary formulations or variations of these materials to achieve the desired performance characteristics.

To obtain more specific information about the type of sintered metal used in the research article you mentioned, I would recommend contacting the authors directly or referring to other related studies or literature in the diesel particulate filters and emissions control field.