Synthesis and characterization of single phase and low temperature co-fired cordierite glass-ceramics from perlite

• α-Cordierite glass-ceramics sintered below 950 °C is synthesized using perlite.
• The glass-ceramics only contains single-phase α-cordierite crystal.
• Thermal expansion coefficients of α-cordierite glass-ceramics are very close to Si.
• Sintering temperature and holding time promotes transforming of μ- to α-cordierite.
• The glass-ceramics can be used as LTCC substrates.

Single α-cordierite glass-ceramics for low temperature co-fired ceramics (LTCCs) substrates were prepared successfully from perlite as the basic raw material. The glass-ceramics could be highly densified above 850 °C and the α-cordierite being the only crystalline phase precipitated from the glass power sintered within 900–950 °C. With increasing sintering temperature or sintering holding time, μ-cordierite was effectively transformed into α-cordierite, and completely transformed into α-cordierite at 900 °C for 6 h. The synthesized single-phase α-cordierite glass-ceramics possessed low dielectric constants (5.6–6.1), low dielectric losses (0.0019–0.02), appropriate flexural strength (112–117 MPa) and suitable coefficients of thermal expansion (2.56–2.91 × 10− 6 K− 1), which qualify them as a potential material for LTCC substrates application.