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We compare literature data for the isotopic ratios of Zr, Sr, and Ba fromanalysis of single meteoritic stardust silicon carbide (SiC) grains to newpredictions for the slow neutron-capture process (the s process) in metal-richasymptotic giant branch (AGB) stars. The models have initial metallicities Z =0.014 (solar) and Z = 0.03 (twice-solar) and initial masses 2 - 4.5 Msun,selected such as the condition C/O>1 for the formation of SiC is achieved.Because of the higher Fe abundance, the twice-solar metallicity models resultin a lower number of total free neutrons released by the 13C({\alpha},n)16Oneutron source. Furthermore, the highest-mass (4 - 4.5 Msun) AGB stars oftwice-solar metallicity present a milder activation of the 22Ne({\alpha},n)25Mgneutron source than their solar metallicity counterparts, due to coolertemperatures resulting from the effect of higher opacities. They also have alower amount of the 13C neutron source than the lower-mass models, followingtheir smaller He-rich region. The combination of these different effects allowsour AGB models of twice-solar metallicity to provide a match to the SiC datawithout the need to consider large variations in the features of the 13Cneutron source nor neutron-capture processes different from the s process. Thisraises the question if the AGB parent stars of meteoritic SiC grains were infact on average of twice-solar metallicity. The heavier-than-solar Si and Tiisotopic ratios in the same grains are in qualitative agreement with an originin stars of super-solar metallicity because of the chemical evolution of theGalaxy. Further, the SiC dust mass ejected from C-rich AGB stars is predictedto significantly increase with increasing the metallicity.

Do meteoritic silicon carbide grains originate from asymptotic giant branch stars of super-solar metallicity?