Vol. 12 No. 1 (1979)

Sari. Hubungan Hall-Petch, σt = σi + KD-1/2 diteliti kembali dengan menggunakan aluminium paduan berbutir kasar, besar butir antara 0,069mm dan 0,404 mm, sebagai bahan uji. Hasil penelitian menunjukkan bahwa harga konstanta K dari perhitungan teoritik dan dari percobaan mempunyai kesesuaian yang tinggi, yaitu perhitungan teoritik K = 0,0514 dan percobaan K = 0,052; tetapi harga eksponen dari percobaan bukannya -0,5 melainkan -1,86. Hubungan antara kekerasan dan kekuatan hasil percobaan sesuai dengan hasil perhitungan teoritik, yaitu hubungan garis lurus dengan konstanta hasil percobaan C =…

. The utilization of cast iron chips as an alternative cheaper raw material in the powder metallurgy industry is currently undergoing development to produce useful products. The present work is concerned with the technology and economy of such as alternative powder processing technique. The mechanical properties of grey cast iron are primarily determined by the proportion of included graphite in the metallic matrix in which the graphite also affects the properties of powdered cast iron chips. The influences of the processing technique on the powder characteristics such as the shape, the size,…

. Industrial waste effluents, particularly from chemical industries, causes pollution. Like other chemical industries, the Letjes Paper Mill (Probolinggo), produce approximately 800 cubic meters of waste effluents per hour, which is directly discharge into the immediate surroundings without any treatment beforehand. The present study was, therefore, undertaken to determine the effects of continous dischargal of the Letjes Paper Mill waste effluents on soil microflora and rice plants. Sari. Buangan industry, terutama dari industri kimia, merupakan penyebab pencemaran. Seperti pula industry…