In powder bed fusion additive manufacturing (AM), the fusing process is temperature and time dependent. However, little work has been done to understand how different processing temperatures and times might impact the mechanical properties at longer sintering times than are typical in laser sintering (LS) systems. Prior results with projection sintering have shown that heating for longer times (>1s) improves part toughness compared to laser sintering. In this work, Large Area Projection Sintering (LAPS) is used to sinter entire layers of material simultaneously over the course of a few seconds with spatial control of layer temperature. This work evaluates the effect of time and temperature on the mechanical properties of parts sintered from PA 2202 (Polyamide 12) powder. Toughness is shown to increase significantly with longer sintering times (5-8 s) and higher temperatures (195-205 °C) with elongations at break (EaB) over 100% and strengths of up to 51.7 MPa. This represents a small increase in strength and an order of magnitude increase in elongation at break relative to LS datasheet values for the material. Peak mechanical properties are achieved sintering at lower temperature (195 °C) and longer times (5-8 s). The density of the samples that maximize toughness and strength is greater than 1.02 g/cm³ compared to datasheet values of 0.98 g/cm³. Porosity elimination could be a mechanism for improved performance though it does not fully explain the improvements in strength and ductility.

在粉末床熔合增材制造（AM）中，熔合过程取决于温度和时间。但是，几乎没有做过什么工作来了解不同的加工温度和时间可能会比激光烧结（LS）系统中的烧结时间长的烧结时间对机械性能产生怎样的影响。投射烧结的先前结果表明，与激光烧结相比，更长的时间（> 1s）加热可提高零件韧性。在这项工作中，大面积投影烧结（LAPS）用于在几秒钟的过程中同时烧结整个材料层，同时对层温度进行空间控制。这项工作评估了时间和温度对用PA 2202（聚酰胺12）粉末烧结的零件的机械性能的影响。烧结时间越长（5-8 s）和温度越高（195-205°C），断裂伸长率（EaB）超过100％，强度达到51.7 MPa，则韧性会显着提高。相对于材料的LS数据表值，这表示强度略有增加，并且断裂伸长率增加了一个数量级。在较低的温度（195°C）和较长的时间（5-8 s）下烧结可获得最高的机械性能。使韧性和强度最大化的样品密度大于1.02 g / cm 在较低的温度（195°C）和较长的时间（5-8 s）下烧结可获得最高的机械性能。使韧性和强度最大化的样品密度大于1.02 g / cm 在较低的温度（195°C）和较长的时间（5-8 s）下烧结可获得最高的机械性能。使韧性和强度最大化的样品密度大于1.02 g / cm³与0.98 g / cm ^3的数据表值相比。消除孔隙率可能是提高性能的一种机制，尽管它不能完全说明强度和延展性的提高。