change integrity - change in physical make-up

gauge - mix in specific proportions; "gauge plaster"

absorb - cause to become one with; "The sales tax is absorbed into the state income tax"

meld, melt - lose its distinct outline or shape; blend gradually; "Hundreds of actors were melting into the scene"

mix in, blend in - cause (something) to be mixed with (something else); "At this stage of making the cake, blend in the nuts"

accrete - grow together (of plants and organs); "After many years the rose bushes grew together"

conjugate - unite chemically so that the product is easily broken down into the original compounds

admix - mix or blend; "Hyaline casts were admixed with neutrophils"

alloy - make an alloy of

syncretise, syncretize - become fused