Kekuatan Tarik Paduan Al 2024-T3 Dan Al 2524-T3 Yang Telah Mengalami Proses Stretching, Chemical Milling Dan Shot Peening

AbstrakPenelitian ini bertujuan untuk mengetahui perilaku uji tarik produk Al 2524-T3 dan Al 2024-T3 yang mengalami proses peregangan, chemical milling dan shot peening. Paduan ini diregangkan melebihi tegangan yeildnya masing-masing 1%, 3% dan 5%, kemudian dilakukan proses chemical milling satu sisi. Etsa yang digunakan dalam proses milling kimia adalah larutan NaOH + Na2S + H2O dengan konsentrasi tertentu. Pada permukaan dilakukan proses shot peening dengan variasi intensitas masing-masing 0,03 A, 0,05 A dan 0,07 A. Material tersebut kemudian diuji sifat mekaniknya dengan uji tarik. Hasil penelitian menunjukkan bahwa tegangan ultimate dan tegangan yield material meningkat dengan meningkatnya persentase regangan. Namun, perpanjangan juga meningkat yang menunjukkan bahwa proses peregangan justru meningkatkan keuletan. Di sisi lain, proses shot peening menurunkan elongasi yang mengindikasikan bahwa proses shot peening menyebabkan penurunan keuletan material. Kata kunci: pengujian tarik, chemical milling, shot peening, stretchingAbstractThis study aims to investigate the tensile test behaviour of Al 2524-T3 and Al 2024-T3 product, which undergoes stretching, chemical milling and shot peening processes. These alloys were stretched beyond yield stress, namely 1%, 3% and 5% of each, and then performed chemical milling process of one side. The etching used in chemical milling process were NaOH+Na2S+H2O solutions with certain concentration. The surface was performed shot peening process with varying intensity of 0.03 A, 0.05 A and 0.07 A respectively. The material then tested its mechanical properties by tensile test. The results show that ultimate and yield stress of material increases with the increase of stretching percentage. However, the elongation has also increased which indicates that stretching process actually increases the ductility. On the other hand, the shot peening process decreases the elongation which indicates that the shot peening process causes a reduction in the ductility of the material. Keywords: tensile tes, chemical milling, shot peening, stretching

Pengaruh Shot Peening Terhadap Kekerasan Dan Kekasaran Produk Chemical Milling Paduan Aluminium Yang Telah Di Stretching

AbstrakPenelitian ini bertujuan untuk mengetahui pengaruh shot peening terhadap kekasaran permukaan produk pembuatan kimia Al 2524-T3 dan Al 2024-T3 yang telah diregangkan. Paduan ini direntangkan melampaui tegangan luluh, yaitu masing-masing 1%, 3% dan 5%, dan kemudian dilakukan proses penggilingan kimia di satu sisi. Etching yang digunakan dalam proses penggilingan kimia adalah larutan NaOH + Na2S + H2O dengan konsentrasi tertentu. Permukaan dilakukan proses shot peening dengan intensitas yang bervariasi masing-masing 0,03 A, 0,05 A dan 0,07 A. Bahan itu kemudian diuji kekasaran permukaan dan kekerasannya. Hasil penelitian menunjukkan bahwa kekasaran permukaan dan kekerasan material meningkat dengan meningkatnya intensitas peening. Namun, ketebalan Al 2524-T3, yang lebih tipis dari Al 2024-T3 menyebabkan tidak signifikannya proses peening shot yang diberikan pada material.. Kata kunci: Shot Peening, Chemical Milling, Kekerasan, Kekasaran Permukaan AbstractThis study aims to investigate the influence of shot peening on hardness and surface roughness of chemical mlling product Al 2524-T3 and Al 2024-T3 which have been stretched. These alloys were stretched beyond yield stress, namely 1%, 3% and 5% of each, and then performed chemical milling process of one side. The etching used in chemical milling process were NaOH+Na2S+H2O solutions with certain concentration. The surface was performed shot peening process with varying intensity of 0.03 A, 0.05 A and 0.07 A respectively. The material were then tested its surface roughness and hardness. The results show that surface roughness and hardness of material increases with the increase of peening intensity. However, the thickness of Al 2524–T3, which is thinner than Al 2024-T3 causing insignificance of the shot peening process given to the materials. Keywords: Shot Peening, Chemical Milling, Hardness, Surface Roughness

Effects of Machining Parameters on the Quality in Machining of Aluminium Alloys Thin Plates

Nowadays, the industry looks for sustainable processes to ensure a more environmentally friendly production. For that reason, more and more aeronautical companies are replacing chemical milling in the manufacture of skin panels and thin plates components. This is a challenging operation that requires meeting tight dimensional tolerances and differs from a rigid body machining due to the low stiffness of the part. In order to fill the gap of literature research on this field, this work proposes an experimental study of the effect of the depth of cut, the feed rate and the cutting speed on the quality characteristics of the machined parts and on the cutting forces produced during the process. Whereas surface roughness values meet the specifications for all the machining conditions, an appropriate cutting parameters selection is likely to lead to a reduction of the final thickness deviation by up to 40% and the average cutting forces by up to a 20%, which consequently eases the clamping system and reduces machine consumption. Finally, an experimental model to control the process quality based on monitoring the machine power consumption is proposed.