The all-new seventh-generation Hyundai Sonata is revealed today in South Korea, ahead of the U.S. version’s debut at next month’s New York International Auto Show.

The Sonata, as expected, gets less-aggressive sheet metal than the sixth-generation model, which was a huge success for Hyundai in the U.S.

The ’10-’14 Sonata grew the brand’s sales in the highly competitive U.S. midsize-sedan segment to more than 200,000 units in a calendar year, reaching a high of 230,605 units in 2012, WardsAuto data shows, and put the Korean automaker in a position of design leadership.

The exterior of the ’15 Sonata follows Hyundai’s Fluidic Sculpture 2.0 philosophy of “simple and harmonious design with refined fluidic design elements.”

Polished lines and forms reflect an “inner dignity,” Hyundai says in a release on the new car, whose U.S. version debuts April 16 in New York.

The Sonata’s nose is more vertical and not creased, with a single-frame 3-D hexagonal grille new for ’15.

The new sedan’s interior also looks radically different from the current model’s, with a more angular center stack a stark change from the curvaceous control area in the current generation car.

Center-stack controls are presented in an easier-to-digest manner, Hyundai says, adding the feel of switches was improved and their distance from the driver shortened.

Unchanged are the Sonata’s powertrains, as the ’15 model keeps the ’14’s 2.0L and 2.4L gasoline-direct-injected 4-cyls.

Transmission choices remain a 6-speed automatic or 6-speed manual.

The Sonata’s overall length grows a couple of inches, while width increases 1 in. (25 mm) and height stays about the same.

Many interior dimensions remain identical although rear-seat legroom gains 1 in.

Hyundai says engineers spent an extensive amount of time refining the car’s ride and handling, with a more rigid chassis a key change from ’14.

Some 51% of the new Sonata is made of advanced high-strength steel, up 30% from the outgoing model, credited for improving the bending and twisting strength of the new-generation car.

Torsional and bending stiffness rises 41% and 35%, respectively, from the ’14 model.

Improved damping makes for a more comfortable ride for occupants, as does changed front- and rear-suspension geometry, the automaker says.

Dual lower rear-suspension arms replace a single-arm design in the current Sonata and “distribute lateral forces more effectively…providing greater freedom to finely tune ride characteristics,” Hyundai says.

Steering improvements come in the form of a larger data-processing unit and a more rigid steering column.

Interior noise is reduced through various measures, including a reinforced firewall with integrated dual-member construction and an undercover with glass-fiber-reinforced polypropylene expansion board material.

The automaker doesn’t disclose fuel economy in today’s release. Last week it made news for giving Korean media an erroneous figure of 29.6 mpg (7.9 L/100 km) combined, not the 28.5 mpg (8.3 L/100 km) Korean government testing showed.

cschweinsberg@wardsauto.com