No abstract

Friction, wear, and corrosion remain the major causes of premature failure of diverse systems including hard-disk drives (HDDs). To enhance the areal density of HDDs beyond 1 Tb/in2, the necessary low friction and high wear and corrosion resistance characteristics with sub 2 nm overcoats remain unachievable. Here we demonstrate that atom cross-talk not only manipulates the interface chemistry but also strengthens the tribological and corrosion properties of sub 2 nm overcoats. High-affinity (HA) atomically thin (∼0.4 nm) interlayers (ATIs, XHA), namely Ti, Si, and SiN x , are sandwiched between the hard-disk media and 1.5 nm thick carbon (C) overlayer to develop interface-enhanced sub 2 nm hybrid overcoats that consistently outperform a thicker conventional commercial overcoat (≥2.7 nm), with the C/SiN x bilayer overcoat bettering all other <2 nm thick overcoats. These hybrid overcoats can enable the development of futuristic 2–4 Tb/in2 areal density HDDs and can transform various moving-mechanical-system based technologies.

Stimuli‐responsive materials can frequently tune between their temporary and original shapes, and have the potential for artificial intelligence‐based technologies in robotics, aerospace, biomedical, engineering, security, etc. Shape memory polymers (SMPs) are promising for these technologies but their inadequate thermal and electrical characteristics causing slow shape recovery limit their practical applications. Herein, for the first time, comprehensively and precisely the shape memory polyurethane (PU), a promising SMP, via a variety of novel layered titanium carbides fillers, namely, Ti2AlC (MAX1), Ti3AlC2 (MAX2), and Ti3C2 (MXene), is engineered. The resultant PU‐composites show 30–50% faster shape recovery in different environments, 20–25% greater extent of shape recovery in the load‐constrained environment, 100–125% higher thermal conductivity, and 700–16 000× higher electrical current. Importantly, the reinforcement of even a small amount of MAX and MXene (such as 0.25 wt%) has largely boosted the performance of PU. Considering ease of processability and performance enhancement factors, the MAX‐phase fillers may be preferred over MXene‐phase fillers for next‐generation composites development. Employing PU composite component as both heat‐sensor and actuator, a unique heat detector/fire alarm device that works successfully in simulated heat and fire environments is demonstrated. This work is crucial for enabling futuristic technologies.