No, “Animal Farm” and “1984” are not a critique of communism; both novels attempt to criticise totalitarianism. In fact, Orwell himself was a Democratic-Socialist; and was actually under the surveillance by the MI5 as a suspected communist. In his part 2 of "The Road to Wigan Pier" Orwell defines: "a real Socialist is one who wishes – not merely conceives it as desirable, but actively wishes – to see tyranny overthrown."
For this reason, even though George Orwell was a socialist, he was also an anti-Stalinist; since he considered Stalin’s government a totalitarian regime. In 1936 he travelled to Spain to fight in the Spanish Civil War against the fascists. However, he did not fight alongside the Spanish Communist Party (PCE) -which was the main communist party at that time- as the PCE supported Stalin. Instead, he joined the Workers’ Party of Marxist Unification (POUM), as they were communists but also anti-Stalinists. During his days in Spain he wrote “Homage to Catalonia”, which praises the benefits of anarcho-syndicalism.
“Animal Farm” is believed to outline the corruption of the communist ideals set by Stalin. And “1984” depicts life under totalitarian rule.