INFINTI QX50: Notable But Unexpected Feature

One of the more notable aspects of the new INFINITI QX50 isn’t what you think.

What you think is probably the 2.0-liter VC-Turbo engine, a variable compression (as in the “VC”). That engine changes its compression ratio as required via a multi-link system that raises or lowers the pistons’ position so as to transform the compression ratio, either providing efficiency for fuel economy or power for performance, as required by the driver.

The 268-hp (@ 5,600 rpm), 280 lb-ft of torque (@1,600 to 4,800 rpm) V6 engine has a compression ratio that varies between 8:1 to 14:1. The adjustments are accomplished via an electric motor with a harmonic drive reduction gear.

The fuel economy is 27 mpg combined for front-drive vehicles and 26 mpg for AWD vehicles, or a 35 percent and 30 percent fuel efficiency improvement compared to a previous V6, respectively.

No, it isn’t that engine. It’s the fact that the 2019 QX50 is claimed to be the world’s first vehicle with body frame parts made with 980 MPa ultrahigh-strength steel, a transformation induced plasticity (TRIP) material.

There is also 1189-MPa steel used in the vehicle.

According to the engineers who developed the tooling for producing parts with this material, shape control was challenging. They observed, “To ensure that shapes could be formed with a high degree of accuracy, we created new forming simulations and designed dies that took into account the specific characteristics of the material.”

And assembly is also different compared with conventional high-strength steel: “We also developed a new set of requirements for the welding process, taking into account the specific characteristics of the material.”

Clearly the INFINITI engineers wanted to make this crossover even more distinct than just in the case of its stylish exterior.