1. In tensile tests, regardless of the testing temperature (20–175°), increasing the copper, magnesium, iron, and nickel concentrations to the highest levels permitted for alloy AK4-1 leads to an increase in the strength of smooth samples and to a lower strength of notched samples. 2. Increasing the concentration of iron and nickel to medium values for alloy AK4-1 (1.14 and 1.17%, respectively) leads to an increase of the time to failure at 135–175° and to a reduction of the time to failure when the concentrations of these elements are at the upper limit (1.4%). The reason for the reduction of the time to failure is the grain refining in the alloy with the maximal concentration of iron and nickel. 3. The time to failure is longest for extruded strips with medium levels of the basic alloying elements. 4. The notch sensitivity of alloy AK4-1 under short-term and long-term static load varies with the iron and nickel content, which determines the quantity of intermetallic phase FeNiAl9 — the notch sensitivity is highest for the alloy with an iron and nickel content at the upper limit and lowest with iron and nickel at the lower limit. 5. To increase the time to failure and reduce the notch sensitivity of alloy AK4-1 during prolonged operation at temperatures of 135–175° it is expedient to limit the concentration of iron and nickel to 0.9–1.15%, keeping the concentration of copper and magnesium at the medium level (2.3 and 1.5%, respectively).