•Closed pore structure is formed in the porous Cu–Sn–Ti metals.•Bonding interface is formed owing to the chemical reaction resultants.•The microstructure of porous Cu–Sn–Ti metals is controlled.•High porosity and satisfactory strength are obtained simultaneously.In order to obtain high porosity and satisfactory strength simultaneously for the porous metallic layer of the grinding tools, alumina bubble particles were added into Cu–Sn–Ti alloy powders to fabricate porous metals using a vacuum sintering method. The influence of the alumina bubble particles on the microstructure and the mechanical strength of the porous Cu–Sn–Ti metal blocks were investigated. Results show that adding alumina bubble particles into Cu–Sn–Ti alloy powder generate closed pore structures for the metal blocks. Good bonding interface between alumina bubble particles and Cu–Sn–Ti alloy is formed mainly dependent on the chemical resultants of TiAl and TiO. A relationship between the bending strength of the porous Cu–Sn–Ti metal blocks and the size and volume fraction of the alumina bubble particles is established.